Write Like a Chemist
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Write Like a Chemist
A Guide and Resource
Marin S. Robinson
Fredricka L. Stoller
Molly S. Costanza-Robinson
James K. Jones
3
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Copyright © 2008 by Oxford University Press, Inc.
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All rights reserved. No part of this publication may be reproduced,
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electronic, mechanical, photocopying, recording, or otherwise,
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Library of Congress Cataloging-in-Publication Data
Write like a chemist : a guide and resource / Marin S. Robinson . . . [et al.].
p. cm.
Includes bibliographical references and index.
ISBN 978-0-19-530507-4 (pbk.)
ISBN 978-0-19-536742-3
1. Chemistry—Authorship—Textbooks. 2. Communication in chemistry—Textbooks.
3. Technical writing—Textbooks. I. Robinson, Marin S.
QD9.15.W75 2008
808'.06654—dc22
2007038271
987654321
Printed in the United States of America
on acid-free paper
Dedicated to
Jeff and Bill,
Chuck and Ronnie,
and Kara
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Preface
Write Like a Chemist is designed to be used as a textbook in upper division and
graduate-level university chemistry classes and as a resource book by chemistry
students, postdocs, faculty, and other professionals who want to perfect their
chemistry-specific writing skills. To this end, Write Like a Chemist focuses on four
types of writing:
■
The journal article
■
The conference abstract
■
The scientific poster
■
The research proposal
Each type of writing, or genre, is directed toward a distinct audience and written
for a different purpose. For example, writing a journal article requires a style and
organizational format that are quite different from that of a research proposal.
Thus, to write like a chemist requires learning to write for multiple audiences
and purposes.
One of the best ways to learn to write like a chemist is to read like a chemist.
Indeed, many of today’s chemists taught themselves to write by reading others’
works and using those works as templates for their own writing. Corrections
(often in red pen) from peers, mentors, reviewers, and editors along the way also
played an integral role in the learning-to-write process. Although ultimately successful, this approach was often painful and inefficient for all involved. The goal
of Write Like a Chemist is to teach writing in a more systematic way. Because
reading is integral to writing, we use the chemical literature (and other examples of writing) to model conventional writing practices; indeed, more than 250
excerpts from ACS journal articles and NSF CAREER proposals are included in
this book. But we do not stop there. Write Like a Chemist endorses a read-analyzewrite approach that combines the reading of authentic passages with the analysis
of those passages to gain insights into the writing conventions of the targeted
genres. Reading and analysis activities are followed by structured writing tasks,
culminating in authentic writing assignments, using the excerpts as models.1
Before going to press, Write Like a Chemist was piloted at 16 U.S. colleges and
universities. The book was used successfully in a variety of instructional settings
(including writing-dedicated courses and lecture, lab, and seminar courses) with
a broad cross section of students, including non-native English speakers and students from multicultural backgrounds. Although intended primarily for chemists, the book will also benefit chemistry majors who ultimately decide to pursue
other careers. Indeed, learning to write in a well-organized and concise manner
requires writing skills that are highly coveted across many fields. Moreover, the
read-analyze-write approach featured in Write Like a Chemist is readily transferable to other disciplines.
Because it will take more than a single encounter with Write Like a Chemist to
become a skilled writer, the book can serve as a rich resource over the years when
the goal is to communicate effectively in writing with chemists, other scientists,
and funding agencies.
Contents
Following the introductory chapter 1, section 1 of Write Like a Chemist is divided
into three modules:
Module 1: The Journal Article (chapters 2–7)
Module 2: The Scientific Poster (chapters 8–10)
Module 3: The Research Proposal (chapters 11–15)
Each module combines authentic readings with exercises to introduce and reinforce discipline-specific writing skills. At the core of each module is a multistep
writing assignment, guided by “Writing on Your Own” tasks, that assists writers
in completing the type of writing emphasized in the module.
Section 2 of Write Like a Chemist includes three chapters that focus on skills
that run across different types of chemistry writing. These chapters guide writers
in formatting and finalizing their written work:
Chapter 16: Formatting Figures, Tables, and Schemes
Chapter 17: Formatting Citations and References
Chapter 18: Finalizing Your Written Work
Write Like a Chemist concludes with two appendices. Appendix A provides helpful tips about language areas that often prove troublesome for writers (e.g., easily
confused words, scientific plurals, punctuation, and grammar). Each language
tip includes exercises and an answer key, facilitating self-study. (For a full listing
of tips, see the first page of appendix A.) For ease of consultation, appendix B
viii
Preface
replicates flow charts (called “move structures” in the book) that illustrate the
typical organization of sections of the genres that are emphasized in the book.
The Write Like a Chemist Web Site
Accompanying the textbook is the Write Like a Chemist Web site (http://www.
oup.com/us/writelikeachemist). Notable features of the Web site include the
following:
■
Web exercises: To prevent users from needlessly retyping full exercises that
only need editing, we have duplicated these exercises on the Web site. In this
way, students can copy and paste the exercises into a text document and edit
them accordingly.
■
“Canned” research projects: We recognize that not all users of this textbook
will have a sufficiently robust research project to write about. To date, we
have developed four “canned” research projects to address this need. These
projects, all based on authentic research, provide sufficient data and background information for a mock journal article or poster.
■
Peer-Review Memo forms: Writing benefits from peer review. To facilitate this
process, we include Peer Review Memo forms, with a list of guided questions
and prompts, for each major section of the journal article.
■
Full-color posters: Module 2 of the book (“The Scientific Poster”) includes
examples of posters in only black-and-white, but full-color versions of these
posters are available at the Web site.
■
Faculty resources: An answer key and examples of analytical and holistic
grading rubrics for major writing assignments (journal-quality paper, poster,
and research proposal) are available at the Web site for faculty adopting the
book.
Unique Features of Write Like a Chemist
Write Like a Chemist is unique in many ways, not the least of which is the fact
that it was conceived by a chemist (M.S.R.) and an applied linguist (F.L.S.) and
developed with additional help from faculty and students in both disciplines. As
part of our interdisciplinary effort, we analyzed chemistry-specific writing practices using tools from corpus linguistics, a discipline that investigates language
empirically through computer-based analyses of large collections of texts known
as corpora (or corpus, singular).2 A 1.5-million-word corpus of chemistry texts was
created, comprising 200 full-length refereed journal articles and 240 sections of
Preface
ix
refereed journal articles (i.e., 60 abstracts, Introduction, Methods, Results and
Discussion sections) from Anal. Chem., Biochemistry, J. Am. Chem. Soc., J. Org.
Chem., J. Phys. Chem. A & B. This database was used to identify common, generalizable patterns3 in the language of chemistry, a task that would have been virtually impossible without the help of the computer. Later on in the project, the ACS
Journals Search (http://pubs.acs.org) was used extensively to accomplish many of
the same aims. Findings from both corpora are included here.
Icons Used in Write Like a Chemist
Icons, each one with a special meaning, are used throughout the book:
Exercises
Exercises that are also posted on the Write Like a Chemist Web site
Definition of a key term or concept
Reminders and/or elaboration of important points
Writing on Your Own tasks (chapters 2–18) and proofreading tips
(appendix A)
Reference to a later part of the book for additional information and/or
practice
Reference to an earlier part of the book for additional information
Explanation of a scientific term or concept
Findings from computer-based analyses of the language of chemistry
A useful principle (i.e., rule of thumb) with broad applications
“Road map” to research proposal (module 3) with enumeration of typical
headings
x
Preface
Writing Conventions Used in Write Like a Chemist
The original text, tables, and figures in this book generally follow Oxford
University Press writing conventions, for example,
■
Initial paragraphs of sections are not indented but subsequent paragraphs
are indented.
■
The “F” in figure and “T” in table are in lowercase when calling out a table
or figure in the text (e.g., see table 1).
■
In tables, column headings are written in title case (e.g., Verb Tense); labels
are bolded with no period (e.g., Table 1 Rates.).
The works cited in this book (i.e., excerpts from ACS journal articles, conference abstracts, and research proposals) are reproduced as written with only slight
modifications as needed to adhere to journal-specific (according to the journal’s
Information for Authors) or ACS guidelines (according to The ACS Style Guide 3rd
ed.), for example,
■
Initial paragraphs are indented or not, as they were in the original source.
■
The “F” in figure and “T” in table are capitalized when calling out a table or
figure in the text (e.g., see Table 1).
■
Tables and figures are reproduced as written; hence, different formatting
conventions are observed (e.g., some table column headings are in lowercase,
others are in title case).
■
Table titles and figure captions are reproduced as written; hence, different
formatting conventions are observed (e.g., some table titles are centered,
bolded, and in title case; others are left-justified, unbolded, and in sentence
case).
Because writing conventions vary and are likely to change with time, we urge
readers to consult the journal of their choice as they prepare manuscripts for
publication.
We wish you good luck. With this book and hard work, you too will be able
to write like a chemist!
Notes
1. Although ours is the first chemistry-specific writing textbook and resource that we
know of that approaches the reading and analysis of chemistry writing in this way, we
have been inspired by a wide body of research into the genres of various fields (e.g.,
Bhatia, 1993, 2004; Connor and Mauranen, 1999; Hill, Soppelsa, and West, 1982;
Preface
xi
Huckin, 1987; Hyland, 1994, 1996, 1998, 2002, 2004a, 2004b, 2006; Johns, 2002;
Paltridge, 1997; Swales, 1990, 2004).
2. Of considerable influence were the following publications: Biber, Conrad, and Reppen
(1994, 1998) and Bowker and Pearson (2002).
3. Note that we do not always use conventional linguistic terminology when discussing
and presenting language-related issues in this book. Rather, we use terminology that
best reaches our intended audience (i.e., chemists).
xii
Preface
Acknowledgments
We gratefully acknowledge the National Science Foundation for financial support of the Write Like Chemist project (DUE 0087570 and DUE 0230913). We are
also indebted to Jeremy Lewis, Acquisitions Editor at Oxford University Press,
and Eric Slater, Copyright Manager of the American Chemical Society, for their
ongoing support of this project. We also thank Paul Hobson, Production Editor,
and Edward (Ned) Sears, Editorial Assistant, at Oxford University Press, as well
as Patricia Watson, copyeditor.
We are grateful to many individuals at Northern Arizona University who contributed to this project. In particular, we thank William Grabe and Bradley Horn
for developing and coordinating project assessment efforts, Sharon Baker for
making thoughtful contributions to the answer key, John Rothfork for developing the project Web site, and Liz Grobsmith for providing institutional support.
We are also indebted to CHM 300W and CHM 610 students who endured early
drafts of the book, in particular, Jennifer Broyles, Lana Chavez, Kevin Pond, and
Catherina Salanga.
This project would not have succeeded without additional support and inspiration from many other individuals at Northern Arizona University and elsewhere, including Geoffrey Chase, Beverly Cleland, Ann Eagan, Julie Gillette,
Kris Harris, Victor O. Leshyk, Alan Paul, Martha Portree, Kurt Ristinen, Paul
Torrence, and Kierstin Van Camp-Horn, as well as the Departments of Chemistry
& Biochemistry and English and the Colleges of Engineering & Natural Sciences
and Arts & Letters at Northern Arizona University.
We are particularly indebted to chemistry faculty (and their students) who
piloted drafts of Write Like a Chemist at their home institutions during 2004–2006
(if faculty affiliations have changed, we note the pilot institution in parentheses):
Frances Blanco-Yu
Seton Hill University
David Collins
Colorado State University–Pueblo
Ellen R. Fisher
Colorado State University
Brian Gilbert
Linfield College
Alex Grushow
Rider University
Angela Hoffman
University of Portland
Timm Knoerzer
Nazareth College
Daphne Norton
Emory University
Donald Paulson
California State University–Los Angeles
Dan Philen
Emory University
Jennifer N. Shepherd
Gonzaga University
Betty H. Stewart
Midwestern State University (Austin College)
Joe Vitt
University of South Dakota
Carl Wamser
Portland State University
Barry L. Westcott
Central Connecticut State University
We also thank faculty who served as external evaluators for the Write Like
a Chemist project:
Jeanne Arquette
Maricopa Community College
Troy Cahou
Coconino Community College
Larry Eddy
Yavapai Community College
Don Gilbert
Northern Arizona University
Sibylle Gruber
Northern Arizona University
Hans Gunderson
Northern Arizona University
Cynthia Hartzell
Northern Arizona University
Pierre Herckes
Arizona State University
Jani Ingram
Northern Arizona University
David F. Nachman
Maricopa Community College
John Pollard
University of Arizona
Scott Savage
Northern Arizona University
Michael Scott
Maricopa Community College
Paul Smolenyak
Yavapai Community College
Diane Stearns
Northern Arizona University
Timothy Vail
Northern Arizona University
We also acknowledge other colleagues who reviewed the book and offered feedback or contributed quotes to the book:
xiv
Joseph H. Aldstadt
University of Wisconsin–Milwaukee
Kevin Cantrell
University of Portland
Bert D. Chandler
Trinity University
Joan Curry
University of Arizona
Acknowledgments
Robert Damrauer
University of Colorado–Denver
Charles H. DePuy
University of Colorado–Boulder
Mari Eggers
Little Big Horn College
Dave Goodney
Willamette University
Nora S. Green
Randolph-Macon College
Suzanne Harris
University of Wyoming
Ann M. Johns
San Diego State University
David B. Knaff
Texas Tech University
Carol Libby
Moravian College
Richard Malkin
University of California–Berkeley
Charlotte Otto
University of Michigan
Pete Palmer
San Francisco State University
Bradley F. Schwartz
Southern Illinois University School
of Medicine
Grigoriy Sereda
University of South Dakota
Steve Singleton
Coe College
Gerald Van Hecke
Harvey Mudd College
Gabriela Weaver
Purdue University
James B. Weissman
Pfi zer Pharmaceutical Marketing
Thomas J. Wenzel
Bates College
Barry L. Westcott
Central Connecticut State University
We gratefully acknowledge the American Chemical Society Publications Division
for granting us permission to use numerous excerpts from journal articles published by the American Chemical Society (including words, phrases, sentences,
one or more paragraphs, titles, figures, tables, and, in one instance, a full article). All selections were reprinted with permission from the American Chemical
Society, granted by Eric S. Slater, Esq., copyright manager. A citation accompanies each selection (e.g., “from Boesten et al., 2001” or “adapted from Boesten
et al., 2001”), and the corresponding bibliographic information is included in the
reference list of cited works at the end of the book.
We also thank the following individuals for granting us permission to use excerpts
from their research proposals or ACS conference abstracts:
Primary Investigator of an ACS Division of Analytical
Chemistry Graduate Fellowship
Amanda J. Haes
Acknowledgments
University of Iowa
xv
Primary Investigators of NSF CAREER Awards
Diana Aga
State University of New York–Buffalo
Daniel J. Dyer
Southern Illinois University–Carbondale
Howard Fairbrother
Johns Hopkins University
Nathaniel Finney
University of California–San Diego
Anna D. Gudmundsdottir
University of Cincinnati
Karen S. Harpp
Colgate University
Paul Hergenrother
University of Illinois–Urbana-Champaign
Robert P. Houser
University of Oklahoma
Jeffrey S. Johnson
University of North Carolina–Chapel Hill
Gary R. Kinsel
University of Texas–Arlington
Amnon Kohen
University of Iowa
Jeehiun Katherine Lee
Rutgers University
Gary A. Lorigan
Miami University
L. Andrew Lyon
Georgia Tech Research Corporation
David L. Patrick
Western Washington University
Christoph G. Rose-Petruck
Brown University
Andrei Sanov
University of Arizona
Eileen M. Spain
Occidental College
Mark E. Tuckerman
New York University
James R. Vyvyan
Western Washington University
Robert A. Walker
University of Maryland–College Park
Timothy H. Warren
Georgetown University
Corresponding Authors of American Chemical Society
Conference Abstracts
xvi
Joseph T. Bushey
Syracuse University
Gerald B. Hammond
University of Louisville
Arthur Lee
Wyeth Research
Athanasios Nenes
Georgia Institute of Technology
Catherine C. Neto
University of Massachusetts–Dartmouth
Peter S. Nico
Lawrence Berkeley National Laboratory
Denis J. Phares
University of Southern California
Cynthia Rohrer
University of Wisconsin-Stout
Acknowledgments
Lynn Russell
Scripps Institution of Oceanography,
University of California–San Diego
Kevin M. Smith
Louisiana State University
Yuegang Zuo
University of Massachusetts–Dartmouth
Finally, we thank Dr. Roald Hoffmann for permission to reproduce his poem
“Next Slide Please” from The Metamict State (1987; Orlando: University of Central
Florida Press, pp 51–52).
The opinions, findings, conclusions, and recommendations expressed in this
book are those of the authors and do not necessarily reflect the views of the
National Science Foundation, the American Chemical Society, or authors whose
works are included in Write Like a Chemist.
Acknowledgments
xvii
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Contents
Section 1
Writing Modules
Chapter 1 Learning to Write Like a Chemist 5
Module 1
The Journal Article 31
Chapter 2 Overview of the Journal Article 33
Chapter 3 Writing the Methods Section 57
Chapter 4 Writing the Results Section 111
Chapter 5 Writing the Discussion Section 163
Chapter 6 Writing the Introduction Section 199
Chapter 7 Writing the Abstract and Title 241
Module 2
The Scientific Poster 271
Chapter 8 Writing the Conference Abstract and Title 273
Chapter 9 Writing the Poster Text 293
Chapter 10 Designing the Poster 335
Module 3
The Research Proposal
357
Chapter 11 Overview of the Research Proposal 359
Chapter 12 Writing the Goals and Importance Section 387
Chapter 13 Writing the Experimental Approach Section 433
Chapter 14 Writing the Outcomes and Impacts Section 479
Chapter 15 Writing the Project Summary and Title 501
Section 2
Graphics, References, and Final Stages of Writing
Chapter 16 Formatting Figures, Tables, and Schemes 523
Chapter 17 Formatting Citations and References 543
Chapter 18 Finalizing Your Written Work 569
Appendix A
Language Tips 583
Audience and Purpose
584
Writing Conventions
601
Grammar and Mechanics 612
Word Usage 634
Appendix B
Move Structures 659
Sources of Excerpts 667
References 685
Index 687
xx
Contents
Write Like a Chemist
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Section 1
Writing Modules
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1
Learning to Write Like a Chemist
Writing, more than any other skill developed as a chemistry
student, has enabled me to advance my career.
—James B. Weissman, Pfi zer Pharmaceutical Marketing
Chapter 1 introduces the basic approach to reading and writing in chemistry
used in this textbook. It also provides a brief orientation to the textbook. By the
end of this chapter, you should be able to do the following:
■
Identify common writing genres in chemistry and in this textbook
■
Describe the five essential components of genre analysis and explain why
genre analysis is so useful for developing writers
■
Explain what is meant by audience, and identify the audiences addressed in
this textbook
■
Differentiate between broad and fine organizational structure
■
Explain the meaning and significance of a move and a move structure
■
Understand how the textbook is organized and the approach it takes to help
you improve your chemistry writing skills
Many effective writers develop their discipline-specific writing skills by reading and analyzing the works of others in their fields. Learning to write in chemistry is no exception; chemistry-specific writing skills are developed by reading and
analyzing the writing of chemists. We coined the phrase “read-analyze-write” to
describe this approach and promote this process throughout the textbook. In this
chapter, we lay the foundation for the read-analyze-write approach by analyzing a
few common, nonscientific examples of writing. We use these everyday examples
(e.g., letters, recipes, jokes, used-car ads, poems) to introduce you to the process
of analyzing writing and to share with you the tools that you will need to analyze
chemistry writing in subsequent chapters.
Genre
I had no idea how much time I would spend writing in my career as
a chemistry professor at an undergraduate institution. With course
materials, grant proposals, and research papers, I am always writing
something.
—Thomas J. Wenzel, Bates College
Unless you are reading this chapter very early in the morning, you have likely
already encountered several different types of writing today. Newspaper articles,
e-mail messages, novels, letters, and billboards are just a few examples of writing
that people view on a daily basis. You may also have glanced at some chemistry-specific writing in textbooks, lab manuals, course notes, reference books, or
chemical catalogs. Each of these types of writing is unique and distinguishable
from the others. This is true even if they share overlapping content. For example,
information about the chemical properties of ethanol is presented differently in
an organic chemistry textbook, a chemical catalog, and a chemical dictionary.
The word used to describe these different types of writing is genre. For example, there are different genres in literature (e.g., poems, short stories, or romance
novels) and in film (e.g., comedy, horror, or mystery films). There are also different genres in chemistry. Although the word may sound a little funny at first, you
will soon see that recognizing a chemistry genre is the first step toward writing
successfully in that genre.
Genre
A type of writing that is distinguished from other types of writing because of differences in
content, form, style, audience, purpose, and context.
This textbook focuses on four distinct genres commonly read and written by
chemists; the four genres are addressed in these three textbook modules:
■
Journal Article (module 1)
■
Scientific Poster and conference abstract (module 2)
■
Research Proposal (module 3)
Exercise 1.1
Make a list of five genres that a college student majoring in chemistry might read
or write. Make a second list with three to five genres that a professional chemist
6
Writing Modules
in academia, industry, or a government lab might read and write. How do these
genres differ from one another?
At the core of the read-analyze-write approach is genre analysis, a systematic
way to read and analyze writing. Through genre analysis, you will identify and
examine essential components of a genre, thereby facilitating your ability to write
effectively in that genre. This textbook focuses on five such components: audience
and purpose, organization, writing conventions, grammar and mechanics, and
science content. As shown in table 1.1, each component can be further divided
into two or more subcomponents. Our goal is to teach you to analyze chemistryspecific writing according to these components and subcomponents. To get you
started, and to illustrate how genre analysis works, we begin by identifying each
component in some familiar (nonchemistry) types of writing.
Genre Analysis
A systematic way of analyzing a genre to identify its distinguishing features.
Audience and Purpose
Before you begin to write, you must decide the audience that is most likely to read
your work and the reason or purpose for writing it in the first place. In turn, the
audience and purpose will influence the levels of detail, formality, and conciseness
that you use in your writing and the words that you choose. To illustrate this, consider two everyday genres: a recipe in a cookbook and a shopping list. The recipe
is written to instruct a hopeful chef (audience) how to prepare a meal (purpose);
the shopping list is written to remind a shopper (audience) what foods to buy
Table 1.1 Components of genre analysis addressed in this textbook.
Audience and
Purpose
Organization
Writing
Conventions
Grammar and
Mechanics
Science
Content
Conciseness
Broad structure
Abbreviations
and acronyms
Parallelism
Graphics
Level of detail
Fine structure
(“moves”)
Formatting
Punctuation
Text
Level of formality
Verb tense
Subject–verb
agreement
Word choice
Voice
Word usage
Learning to Write Like a Chemist
7
(purpose). Because of their different purposes, detailed instructions are needed
in the recipe but not in the shopping list. (Imagine how useless a recipe would be
if it included only a list of ingredients or how unwieldy a shopping list would be
if it included instructions for locating each item in the store!) Moreover, because
recipes are often published, the writing is more formal, with titles, headings, lists
of ingredients presented in a parallel fashion, and unambiguous, fully punctuated
sentences (e.g., Melt 2 tsp. butter in a small saucepan.). Shopping lists, on the other
hand, are scrawled out in personal shorthand (e.g., choc, OJ, mlk) with no titles,
headings, or punctuation. Thus, we can see how audience and purpose influence
the levels of detail, formality, and conciseness of a particular genre.
Audience
The people who will most likely read a specific piece of writing.
Purpose
The aims, goals, or intentions of the writer.
As a second example, consider two genres of letters: a job application cover
letter and a sympathy letter to a friend. These two types of letters are sent to different individuals (audience) with whom the writer has different relationships and
for entirely different reasons (purpose). These differences are reflected not only in
tone (i.e., the job application letter is formal and professional, while the sympathy
letter is personal and compassionate) but also in characteristic phrases. A potential employer would be quite surprised to read an application letter signed “Love,
Mario” as would a friend reading a sympathy letter beginning with “To Whom It
May Concern.” Word choices such as these are anticipated by readers. Choosing
the right word is not easy (see figure 1.1). If expected words are missing, or a wrong
phrase is used, readers will have a difficult time following, or even recognizing,
the genre. Hence, by learning words and phrases that are characteristic of a genre,
you can make your own writing sound more like a typical example of that genre.
Figure 1.1 Even Snoopy struggles for just the right words. PEANUTS: ©United Feature Syndicate, Inc.
8
Writing Modules
Word Choice
Readers expect characteristic words and phrases to be used in a genre (e.g., the word
“Discussion” is used to demark the start of a journal article Discussion section). Effective
writers must learn to incorporate these words into their writing.
Keep in mind that both audience and purpose define a genre. Two pieces of
writing with the same intended audience may be written very differently if they
have different purposes. For example, a university catalog and a university student newspaper are both written for a student audience, but the two publications
are distinct from one another in many ways (e.g., organization and content).
With these everyday examples in mind, let’s consider audience and purpose
for chemistry-specific genres. We begin with audience. Chemists write for many
different audiences, including students, teachers, and Ph.D. chemists, to name
only a few. Thus, it is instructive to divide audience into different categories.
For our purposes, we consider four categories: the expert audience, the scientific
audience, the student audience, and the general audience. The expert audience
includes professional chemists with advanced knowledge in a subdiscipline of
chemistry, such as biochemistry, analytical chemistry, or organic chemistry. The
subdiscipline is often reflected in the name of the journal written for experts in that
field (e.g., Biochemistry, Analytical Chemistry, or The Journal of Organic Chemistry).
The scientific audience comprises readers with scientific backgrounds but not
necessarily in the authors’ field or subdiscipline. For example, a biologist or geologist asked to review a chemist’s research proposal would be considered a scientific
audience. The student audience consists of individuals who are reading to learn
chemistry at any level, such as a high school student reading an introductory
chemistry book or a graduate student studying a book on quantum mechanics.
The general audience includes readers who are interested in a chemistry topic
but with little to no formal training in chemistry, such as an English or history
teacher reading Science News or Popular Science.
Expert Audience
Readers with expert-level knowledge in a specific area of chemistry.
Scientific Audience
Readers with significant scientific knowledge, but not in the specific area targeted in the
written work.
Learning to Write Like a Chemist
9
Student Audience
Readers learning chemistry.
General Audience
Readers with little or no chemistry knowledge.
Together, these four audiences form a continuum that spans a wide range of
expertise in chemistry (figure 1.2). In general, journal articles are written for an
expert audience, research proposals and scientific posters for a scientific audience,
textbooks for a student audience, and popular science articles for a general audience. Of course, these pairings are only guidelines. A genre can change position
on the continuum if an audience is expected to have more (or less) chemistry-specific knowledge. For example, a poster presented at a highly technical conference
should address an expert audience, but a poster presented at an undergraduate research conference should target a student or general audience. Moreover, a
single genre often addresses more than one audience. Although a journal article
is written primarily for an expert audience, parts of its Introduction section are
often written for a scientific audience. You can see that determining your audience
is an integral part of the writing process.
In this textbook, we focus on two audiences. In module 1 (“The Journal
Article”) we focus on the expert audience, and in modules 2 and 3 (“The Scientific
Poster” and “The Research Proposal”), we focus on the scientific audience. There
are other genres that target these same audiences, such as technical memos and
reports, but they are not covered in this textbook. An important goal of this
Figure 1.2 A spectrum of genres for audiences with varying degrees of expertise.
10
Writing Modules
textbook is to help you move beyond writing for a student audience (the targeted
audience in many undergraduate lab reports) and begin to write for expert and
scientific audiences.
Closely linked to audience is purpose; a genre is also influenced by the purpose for the writing. Several different purposes for chemistry-specific writing
are listed below. Representative genres are shown in parentheses. This textbook
addresses only the first two of these purposes:
■
To present research results or convey new scientific insights (journal articles
and posters)
■
To request funding (research proposals)
■
To teach or instruct (textbooks)
■
To convey instructions (lab or operating manuals)
■
To provide chemical information (safety data sheets)
■
To communicate with colleagues (memos or e-mails)
Exercise 1.2
Look back at the lists of chemistry genres that you created in exercise 1.1. Who
is the primary audience for each genre: general, student, scientific, and/or expert
audience? Some genres will target only a single audience; others will target a
range of audiences.
Exercise 1.3
What are some characteristics of writing intended for a student audience? Look at
a chemistry textbook. How has the author attempted to address a student audience? Consider features such as examples, illustrations, and definitions, as well as
the type of vocabulary used.
Exercise 1.4
What are some characteristics of writing intended for a general audience? Find
an article in your local newspaper about a science topic. How has the author
attempted to make the article interesting and accessible to nonscientists? Consider
features such as illustrations, the lengths of sentences and paragraphs, descriptive
language, and the use of direct quotes.
Learning to Write Like a Chemist
11
Exercise 1.5
Write a sentence or short statement related to a topic that you are knowledgeable
about (e.g., a hobby, favorite sport, type of music) as if you were writing to a friend
with a similar interest. Then “translate” that sentence (or statement) for a person
who has limited knowledge of the topic.
For example, if you were playing correspondence chess with another person, the
two of you might write the following to depict the first three rounds of moves:
(1)
(2)
(3)
e4
Nf3
Bc4
e5
Nc6
Be2
For a newcomer to correspondence chess, you might translate the chess “shorthand” for the first three (of six) moves as follows:
The first player (white) moves his/her King Pawn (the small white chess piece
immediately in front of the white King) forward two spaces. In reply, the
second player (black) moves his/her King Pawn two spaces forward. In the
second round of moves, white moves his/her King Knight (a larger piece that
traditionally looks like a horse) to the open space immediately in front of the
King Bishop Pawn (the pawn immediately in front of the Bishop, the piece
that stands to the right of the King).
Exercise 1.6
Most readers of this book are already expert enough to interpret the following
notation, which summarizes the 1H NMR spectrum of CH3Br:
1
H NMR (TMS) δ 2.68 (s, 3H)
(If necessary, consult an organic textbook to remind yourself what this notation
means.) Make a list of the concepts that are required to understand the notation.
Which of these concepts would you need to explain to a student starting organic
chemistry that a more advanced student (e.g., a junior-level chemistry major)
would already know?
Organization
The second essential component of genre analysis is organization. If you decide to
write in a particular genre, you implicitly agree to follow the organizational structure of that genre. Such is the case for romance novelists, Disney scriptwriters,
12
Writing Modules
and “whodunit” mystery writers; all must adhere to a time-honored formula (or
risk having their work remain unpublished). Indeed, one of the best ways to learn
to write in a new genre is to analyze the organizational structure of that genre.
Organizational structure can be divided into broad and fine structural features. Broad structural features are indicated, for example, by readily identifiable
sections or headings (e.g., Introduction, Results, and Discussion); fine structural
features are identified by patterns of organization within paragraphs and within
sections (e.g., from more general to more specific) and by transitions between
paragraphs. Both sets of features contribute to the readability and flow of the
written piece. A joke book, for example, can be broadly organized by type (e.g.,
knock-knock jokes, light bulb jokes, genie jokes), but a single joke can also be
organized into finer segments (e.g., opening line, punch line). We can think of
these finer structural features as the many steps (or moves) that writers take to
progress from the beginning to the end of each section of their writing, always
with the purpose of communicating clearly with their intended audience. Writers
who make use of conventional moves in their written work meet the organizational expectations of their intended audience. (Although the move concept, like
the term “genre,” may sound odd, its utility will become clearer as you progress
through the textbook.)
A Move
A step taken by writers to achieve part of their overall purpose. Writers who use conventional moves in their written work meet the organizational expectations of their readers.
The move concept is a bit easier to illustrate with examples; hence, we do this
with two jokes. The overall purpose of a joke is to make the reader (or listener)
laugh. The smaller parts of the joke—the moves—serve as building blocks to
help the teller (writer) achieve the overall purpose of the joke.
The first joke is a “three-men” joke. In table 1.2, the joke itself is in the left-hand
column, the moves are in the center column, and the sentences that accomplish
the moves are in the right-hand column. The joke is told in six moves (or steps):
the joke setup; actions 1, 2, and 3; the punch-line setup; and the punch-line delivery. The second joke is a variation of a “guy-walks-into-a-bar” joke (table 1.3).
(We could not resist this joke because it pokes fun at incorrect punctuation.) The
joke is told in seven moves: the joke setup, a four-step action/reaction sequence
between the guy (panda) and the bartender, the punch-line setup, and the punchline delivery. In both examples, the sequencing of moves plays an important role
in achieving the purpose of the jokes; if the moves were sequenced differently
(e.g., if the punch line were given first), the jokes would no longer be successful.
Thus, the appropriate moves not only must be present but also must be presented
in the correct order.
Learning to Write Like a Chemist
13
Table 1.2 A three-men joke and its moves.
Joke
Moves
Illustration of Moves
Three men on death row are
about to be executed by firing
squad. The first man goes
before the firing squad, but
just as he is about to be shot,
he distracts the squad by
shouting, “Earthquake!” During
the confusion, he makes his
escape. On the next day, the
second man goes before the
firing squad. Just as he is about
to be shot, he distracts them
by shouting, “Tornado!” In the
confusion, he makes his escape.
On the third day, the third man
goes before the firing squad.
Just as he is about to be shot, he
yells “Fire!”
Set up the joke
Three men on death row are about
to be executed by firing squad.
Describe action #1
The first man goes before the firing
squad, but just as he is about to
be shot, he distracts the squad by
shouting, “Earthquake!” During the
confusion, he makes his escape.
Describe action #2
On the next day, the second man
goes before the firing squad. Just as
he is about to be shot, he distracts
them by shouting, “Tornado!” In
the confusion, he makes his escape.
Describe action #3
On the third day, the third man
goes before the firing squad.
Set up the punch line
Just as he is about to be shot, he
yells
Deliver the punch line
“Fire!”
Table 1.3 A variation on a guy-walks-into-a-bar joke and its moves.
Joke a
Moves
Illustration of Moves
A panda walks into a bar and
orders a drink. When he’s done,
he draws a gun and fires two
shots into the air. “What was
that for?” asks the confused
bartender. The panda produces
a badly punctuated wildlife
manual and tosses it over his
shoulder. “I’m a panda,” he says,
at the door. “Look it up.” The
bartender turns to the relevant
entry and, sure enough, finds
an explanation. “Panda. Large,
black-and-white bearlike
mammal, native to China. Eats,
shoots, and leaves.”
Set up the joke
A panda walks into a bar and orders a
drink.
Describe guy action #1
When he’s done, he draws a gun and
fires two shots into the air.
Describe bartender
reaction #1
“What was that for?” asks the confused
bartender.
Describe guy action #2
The panda produces a badly
punctuated wildlife manual and tosses
it over his shoulder. “I’m a panda,” he
says, at the door. “Look it up.”
Describe bartender
reaction #2
The bartender turns to the relevant entry
and, sure enough, finds an explanation.
Set up the punch line
“Panda. Large, black-and-white
bearlike mammal, native to China.
Deliver the punch line
Eats, shoots, and leaves.”
a. Joke adapted from Truss (2003).
14
Writing Modules
1. Set up the Joke
2. Describe an Action
Repeat (as needed)
3. Set up the Punch Line
4. Deliver the Punch Line
Figure 1.3 A visual representation of the move structure
for a typical three-men joke.
Note that the moves and their sequencing are quite similar in both jokes, but
because the jokes come from two different genres, they are not identical. (Even
jokes within the same genre can have slight variations in moves.) The major
difference is in the action steps: the three-men joke reiterates the action three
times (once for each man); the guy-walks-into-a-bar joke reiterates the guy action/
bartender response sequence twice.
In addition to listing the moves, as we did in tables 1.2 and 1.3, moves can also
be represented graphically using a diagram similar to a flow chart. Such a diagram
is called a move structure. A move structure illustrates required moves, optional
moves (when appropriate), and the sequence of moves, including any repeated
move patterns. A move structure for the three-men joke is illustrated in figure 1.3.
Note that, in the move structure, the three action steps (the second move) comprise a single move that is reiterated as needed (in this case, three times).
Move Structure
A flowchart-like representation of the moves within a genre. The diagram visually depicts
required and optional moves, illustrates repeated moves, and shows the sequencing of
moves.
Exercise 1.7
Using figure 1.3 for guidance, propose a move structure for the panda version of
the “guy-walks-into-a-bar” joke shown in table 1.3.
Learning to Write Like a Chemist
15
Table 1.4 Analyzing the moves present in used-car ads.
Car Ad
Information Presented
1995 Ford Aspire, great mpg, good reliable car,
$2000. Call 774–3972
Year, make, model, subjective description, price,
phone number
94 Ford Mustang conv GT, 5.0L, 5sp, new tires
$7200/obo. David 526–0240
Year, make, model, special features, price, name,
phone number
88 Ford Taurus wagon, good cond, $2200/obo.
213–1327 evenings
Year, make, model, subjective description, price,
phone number, when to call
94 Chrysler LaBaron, red, 142K, sporty, fun,
looks/runs grt, $2300 Josh 226–1260
Year, make, model, special features, subjective
description, price, name, phone number
1995 Ford Taurus GL, 117K, air bags, 3.0L V6,
great running cond, $1600. 522–8272
Year, make, model, special features, subjective
description, price, phone number
92 Pontiac Bonneville SSEi, good cond, runs
well, 130k mi, asking $2700/firm. 600–1721
Year, make, model, subjective description, special
features, price, phone number
We next analyze the moves and move structure for another common genre: the
used-car ad. Several examples of newspaper used-car ads are shown in table 1.4.
As you examine these ads, you will likely notice that certain information—the
year, model of the car, price, and a phone number for contacting the seller—is
contained in every ad. Other types of information—such as car features and
seller’s name—appear in only some of the ads. To keep track of the information,
and how often it appears, we list the contents of each ad in the second column in
table 1.4. Some combination of this information is needed for the seller to achieve
his or her purpose (i.e., to sell the car).
Using the information in table 1.4, the used-car ad can be divided into five moves.
In the first move (included in all six ads), the seller states the essential facts about
the car (year, make, and model). In the second move (included in all but two ads),
the seller highlights select features of the car (e.g., new tires, air bags, five speeds).
In the third move (interchangeable with the second), the writer offers a subjective
description of the car (e.g., “good cond” or “fun”). In the fourth move, the writer
states the price. Finally, in the fifth move, the seller provides contact information:
(1) a phone number, (2) a contact name (optional), and (3) when to call (optional).
A move structure that depicts these moves is shown in figure 1.4. Important
features about this move structure (and other move structures in this textbook)
include the following:
16
■
A box is placed around each move.
■
Some moves are divided into submoves (e.g., moves 1 and 5).
■
Moves and submoves are numbered to convey their conventional order in
the genre. Occasionally, moves are placed side by side (e.g., moves 2 and 3).
Writing Modules
1. State Objective Facts
1.1 State year
1.2 Report make
1.3 Indicate model
3. Offer Subjective Description
2. Identify Select Features
(if applicable)
(e.g., new tires, all bags, mileage)
(optional)
(e.g., car condition)
4. State Price
5. Provide Contact Information
5.1 Give seller's name (optional)
5.2 Include phone number
5.3 State when to call (optional)
Figure 1.4 A visual representation of the move structure for a typical used-car ad. Moves
that are side by side can occur in either order.
This indicates that the moves can be addressed in either order. (Submoves
that can occur in any order are also placed side by side in boxes but are not
numbered.)
■
Each move and submove begins with an action verb (e.g., state, identify,
provide).
■
Unless stated otherwise, a move or submove is required; without the move
or submove, the genre would be incomplete and ineffective (e.g., imagine a
used-car ad that omits the make of the car).
■
Some moves or submoves are not required in all instances. Such moves and
submoves are followed by the words if applicable or optional (in parentheses). If applicable indicates that the move is required only when appropriate.
For example, if a car has special features, the seller should mention them;
otherwise, the move should be skipped. Optional indicates that the move is
left to the discretion of the writer. For example, in the used-car ad, sellers
can decide whether to state their cars’ condition, their names, or when to call.
Required Moves
Most moves are required; that is, the genre would be incomplete or unrecognizable
without them.
Learning to Write Like a Chemist
17
Occasionally, moves or submoves are required only in some instances or are left to the
discretion of the writer. We label such moves if applicable and optional, respectively.
Analogous move structures are used throughout this textbook to illustrate
major sections of the journal article, poster, and research proposal. The move
structures are meant to guide you in reading and writing these genres. Like the
used-car ad, most moves are required, but a few are not. For example, in the
Methods section of a journal article, the move “Describe Numerical Methods” is
labeled if applicable (see figure 3.1) because not all authors use numerical methods
in their work. Similarly, the submove “preview key findings” in the Introduction
section is labeled optional (see figure 6.1) because it is the author’s prerogative to
include that move or not. Of course, we cannot possibly know what is applicable
for all individuals reading this textbook, so, as a writer, you will need to decide for
yourself which moves and submoves are most relevant for your own purposes.
Exercise 1.8
Moves highlight the fine organizational structure of a genre and help to achieve
the purpose of the genre. With this in mind, what is the purpose of the usedcar ad genre? Could you achieve this purpose if your ad was missing one of the
required moves? On the other hand, if your ad contains all of the required moves,
are you guaranteed to achieve your purpose?
The Right Answer?
Exercise 1.8, like many exercises in this textbook, is designed to get you thinking about
writing; hence, it will have several “right” answers (although some answers may be better
than others).
Writing Conventions
Every genre has its own writing conventions (the third essential component of
genre analysis), and chemistry-specific genres are no exception. Writing conventions, as the name implies, are generally accepted (and expected) practices;
they are not “right” in the absolute sense (unlike most rules of grammar and
punctuation). Writing conventions are governed by rules of writing that should
be followed within a particular genre but often vary across genres. (Thus, if you
write in more than one genre, you will need to learn the writing conventions for
each genre.)
18
Writing Modules
Writing Conventions
Rules of writing that are followed within a particular genre, but often vary across genres.
Examples include how to format graphics, how to cite references, when to capitalize,
and whether to use past or present tense.
One writing convention that varies across genres is formatting. Consider, for
example, the formatting of business letters; typically either indented paragraphs
or blocked paragraphs separated by spaces are used. These variations in formatting lead to noticeable differences in appearance. Or consider the formatting used
in a telephone book. Lasts names are bolded and in uppercase, followed by a
lowercase first name (e.g., MILLER Albert); for an extra fee, you can request additional bolding and/or a larger font size (e.g., CHICAGO TITLE INSURANCE).
If telephone book entries were formatted differently (e.g., first name followed by
last name), the genre would hardly be recognizable, and the information provided
would be more difficult to access.
Formatting
Writing conventions specific to a genre that dictate the appearance and physical
placement of written elements in, for example, tables, figures, references, headings, and
number/unit combinations.
Chemistry-specific genres also have formatting rules. There are formatting
rules for tables, figures, in-line citations, references, and number/unit combinations, to name only a few. The rules reflect reader expectations with regard to font
size (e.g., in poster titles), bolding (e.g., in labeling, where 1 can be used to represent a chemical compound), italics (e.g., in references, where volume numbers are
italicized), and placement (e.g., in citations, where numbers are superscripted).
The rules also dictate whether or not to include a space between a number and
its unit. For example, which is correct: 10mm or 10 mm, 100º C or 100 ºC?
Formatting conventions will help you answer this question.
The use of abbreviations and acronyms is another writing convention that varies across genres. In every genre, we see abbreviations and acronyms for words
and phrases that are used repeatedly in that genre (and often, these abbreviations
appear to be a foreign language to newcomers to that genre). For example, the shopping list uses “choc,” OJ,” and “pb” for chocolate, orange juice, and peanut butter,
respectively; the used-car ad uses “mpg,” “sp,” and “obo” for “miles per gallon,”
“speed,” and “or best offer,” respectively. To write effectively in chemistry, you need
to learn the standard abbreviations. Although you may already be familiar with “m”
for meters and “g” for grams, you may be less familiar with “µg” for micrograms and
Learning to Write Like a Chemist
19
“h” for hours. With abbreviations such as these, chemists omit the “s” for plural units
(“g” not “gs” for grams) and seldom use periods (“min” not “min.” for minutes).
Abbreviations and Acronyms
Abbreviations and acronyms are agreed-upon short forms for commonly used words and
units.
When spoken aloud, abbreviations are often pronounced letter by letter (e.g., A-C-S),
whereas acronyms form a pronounceable word (e.g., NASA).
Genres also vary by their conventional uses of verb tense (past, present, or
future) and voice (active or passive voice). For example, most jokes (including the
three-men joke) are told (or written) in present tense (“Three men are . . . about to
be executed” as opposed to “Three people were . . . about to executed”). Present
tense is used to make the joke more vivid for the listener or reader. Jokes also tend
to be told in active rather than passive voice:
Active A panda walks into a bar and orders a drink.
Passive A bar is entered by a panda and a drink is ordered.
In this textbook, we examine how tense and voice are used in journal articles,
posters, and proposals. As we will see, all tenses and both voices are used, depending on which genre, or section of a genre, is being written.
Writing conventions may seem a bit picky to you at this point; however, by
adhering to the writing conventions of chemists, you take an important step toward
sounding like an expert chemist. If you submit a journal article, for example, with
improperly formatted units and figures, incorrect abbreviations, and inappropriate
verb tenses (e.g., present tense in sentences that are conventionally written in past
tense), readers may judge you as a careless scientist and dismiss your work.
Exercise 1.9
Look back at the sentence(s) that you wrote in exercise 1.5. List any special writing conventions that you used. Would others interested in this topic know and
use the same conventions?
Grammar and Mechanics
The fourth component of genre analysis addressed in this textbook relates
to grammar and mechanics. Unlike writing conventions, which vary across
genres, grammar and mechanics are governed by rules that apply to many
20
Writing Modules
formal written genres, though variations exist, for example, in spelling and
punctuation. (The rules may be altered intentionally in creative writing genres
such as poetry or fiction writing.) Although grammar and mechanics are not
the focus of this textbook, we do point out common pitfalls experienced by
novice writers. As shown in table 1.1, these include errors in parallelism,
punctuation, subject–verb agreement, and correct word usage (e.g., affect vs.
effect).
Grammar and Mechanics
Grammar: Rules for combining words into meaningful sentences (e.g., subject–verb
agreement).
Mechanics: Rules for spelling and standard punctuation (including the use of apostrophes,
hyphens, and capitalization).
In general, rules of grammar and mechanics are followed across formal written genres,
though variations exist (e.g., British and American spelling).
Word Usage
The term word usage refers to correct and incorrect uses of words and phrases. For
example, there is a right way and a wrong way to use such words as affect and effect and
spectra and spectrum.
In contrast, the term word choice refers to choosing among several conventionally
accepted words and phrases for a particular audience.
The panda joke (table 1.3), adapted from a bestselling book entitled Eats,
Shoots & Leaves: The Zero Tolerance Approach to Punctuation (Truss, 2003), illustrates the importance of correct punctuation (specifically, the troublesome
comma). How should the punch line be punctuated in the panda joke to provide
a proper definition of a panda? Here is what we recommend:
Punch line Panda. Large, black-and-white bearlike mammal, native to
China. Eats, shoots, and leaves.
Corrected Panda. Large, black-and-white bearlike mammal, native to
China. Eats shoots and leaves.
Like punctuation, the misuse of commonly confused words (e.g., its/it’s, affect/
effect, comprise/compose, fewer/less) can result in miscommunication and
undermine the message conveyed in your writing.
Learning to Write Like a Chemist
21
Exercise 1.10
Consider the following sentences. Choose the correct word in each. What rule
guided your choice? (See appendix A for assistance, if needed.)
a. The human wrist is comprised/composed of eight bones, but the ankle has only
seven.
b. Fewer/Less samples were used in the original series.
c. The new procedure affected/effected the yield.
d. The instrument was chosen for it’s/its detection limits.
Science Content
It goes without saying that having a crystal clear understanding of a
subject is a prerequisite to effectively writing about it.
—Joseph H. Aldstadt, University of Wisconsin–Milwaukee
The fifth and last essential component of genre analysis addressed in this textbook
is science content. It is impossible to write a clear and effective paper if you lack a
clear understanding of the chemistry involved; understanding the chemistry and
writing about that chemistry go hand in hand. Writing is also an effective tool
for learning chemistry. Chemists often “think through their hands” (i.e., through
writing). You will find that as you write about your science, you will gain deeper
insights and knowledge of that science.
Content
The topic(s) covered in a given genre; content is expressed through both text and graphics.
Every genre has rules (often unspoken) restricting appropriate content for
that genre. A joke restricts content by appropriateness; depending on the audience, some content may be viewed as offensive rather than funny. A used-car ad
restricts content by topic (you must advertise a used car, not a used refrigerator)
and by space (you pay by the word, so you describe the car in a precious few lines,
using standard abbreviations). Journal articles also restrict content; a chemistryrelated journal article must be written about novel research in a subfield of chemistry. Although a chemist could write a paper that describes how a cake is baked
(“After mixing, the ingredients were heated in an oven for 60 min at 176 °C.”),
we all know that such a paper would never be published in a chemistry journal,
even if it adhered to all other defining characteristics of that genre. However clear
22
Writing Modules
the organization and writing are, if the content differs from the expectations of
the genre, it will not be recognizable as an instance of the genre. Thus, a genre
requires not only appropriate organization and language, but also appropriate
content.
Content is typically expressed in one of two ways: text (prose, written language)
and graphics (photographs, drawings, figures, etc.). Used-car ads, for example,
may include a photograph of the vehicle, while recipe cards may include pictures
of the prepared dish. Chemistry genres are no exception. Chemists express their
content with graphics (tables, figures, and schemes) in addition to text. One key
to clear chemistry writing is the appropriate and effective use of both forms of
expression. In this textbook, we illustrate how chemists use text and graphics
to communicate content effectively, and how the authors weave back and forth
between the two to tell a story of scientific discovery.
As you analyze the ways in which chemists communicate content, don’t be
surprised if you learn some new chemistry, too. Although the primary focus
of this textbook is writing, we believe that your chemistry knowledge will also
expand as you read, analyze, and write.
Exercise 1.11
Read and analyze the following excerpt from a Material Safety Data Sheet (MSDS)
for barbecue lighting fluid. Comment on as many of the five essential writing
components as you can: audience and purpose, organization, writing conventions, grammar and mechanics, and science content.
SECTION 2: COMPOSITION/INFORMATION ON INGREDIENTSa
HAZARDOUS INGREDIENT NAME
CAS No
CONTENT
RISK
CLASS
Petroleum Distillate (Kerosene)
64742-47-8
99%
R65
Xn
Benzene (CAS No 71-43-2) will not normally be present, but always be less than the 0.1%
w/w marker level in the 21st ATP to the Dangerous Substance Directive. Barbeque Lighting
Fluid is not classified as a carcinogen under 67/548/EEC and the UK CHIP Regulations.
SECTION 3: HAZARDS IDENTIFICATION
INGESTION
Harmful if swallowed in large amounts.
SKIN CONTACT
Unlikely to cause irritation to skin on single
exposure. Prolonged exposure may defat the
skin leading to dermatitis.
EYE CONTACT
May cause irritation and reddening of the eyes.
INHALATION
Vapour at high concentrations may cause
dizziness, headaches, nausea.
Learning to Write Like a Chemist
23
Exercise 1.11 (Continued)
PHYSICAL AND CHEMICAL HAZARDS
Toxic to aquatic organisms, may cause long
term effects in the aquatic environment
a. Adapted from Bird Brand Material Safety Data Sheet. Product: Barbecue Lighting Fluid. http://www.
birdbrand.co.uk/msds/Barbecue%20Lighter%20Fluid.doc (accessed June 2004).
What to Expect
My graduate advisor told me something many times that I now tell my
students: Writing is thinking. In order to truly communicate a scientific
idea in a precise written form, one really needs to think long and hard
about the best way to accomplish that goal.
—Alexander Grushow, Rider University
Each module in Section 1 of this textbook begins with an introduction to the
targeted genre, including an overview of the sections that commonly compose the
genre. The remainder of the module examines each of those sections in greater
depth. For example, module 1, “The Journal Article”, includes an introductory chapter followed by individual chapters dedicated to the different sections of a journal
article: the abstract, Introduction, Methods, Results, and Discussion (although not
in that order). Most chapters begin with an authentic example of the targeted section from the chemistry literature, taken largely from American Chemical Society
(ACS) journals, which you will become quite familiar with by the end of this book.
You are asked to read the example (multiple times) and analyze it for its essential
components (audience and purpose, organization, writing conventions, grammar
and mechanics, and science content). The rest of the module includes excerpts
from the chemistry literature, explanations, and exercises designed to strengthen
your ability to read, analyze, and write in that genre. Interspersed throughout the
chapters are “Writing on Your Own” step-by-step tasks that will guide you in writing in the target genre. While you write, we suggest ways for you to improve your
writing through multiple revisions of your work.
ACS (American Chemical Society)
The premier American professional organization for chemists, chemical engineers, and
other professionals interested in chemistry (http://www.acs.org).
Module 2 (“The Scientific Poster” and conference abstract) and module 3
(“The Research Proposal”) are organized similarly to module 1; they include an
24
Writing Modules
introduction to the genre, authentic examples of the genre, a detailed discussion
of each section composing the genre, and Writing on Your Own tasks. Through
this combination of reading, analyzing, and writing, you will learn to recognize
the defining characteristics of four important genres in the field of chemistry and
to incorporate those characteristics into your own writing of those genres.
Section 2 of the textbook includes chapters that are relevant to the four genres
covered in section 1. In these chapters, you will learn to format tables, figures,
and schemes (chapter 16) as well as citations and references (chapter 17). In the
last chapter (chapter 18), you will find useful hints for the final stages of revision
for all your written work.
Additional language tips—related to audience and purpose, writing conventions, and grammar and mechanics—are included in appendix A. Each tip has
explanatory notes, examples, exercises, and an answer key, making self-study
easy. Appendix B repeats, for easy reference and accessibility, the move structures
included in the textbook.
Chapter Review
As a review of what you’ve learned in this chapter, define each of the following
terms for a friend or colleague who is new to the field of chemistry:
ACS
audience
content
formatting
genre
genre analysis
move
move structure
optional move
purpose
required move
word choice
word usage
writing conventions
Similarly, explain the following to a friend or colleague who has not yet given much
thought to chemistry genres geared toward expert and scientific audiences:
■
Genres commonly used by chemists at various levels in their training
■
Five components of genre analysis and how they facilitate the read-analyzewrite approach to writing in chemistry
■
Audiences that scientific writing typically addresses
■
Common purposes of scientific writing
■
Differences between broad and fine organization
■
Relationship between a genre’s move structure and its organization
■
Examples of formatting, word choice, and word usage that are both appropriate and inappropriate in chemistry-specific writing genres
■
Two different means of communicating science content
Learning to Write Like a Chemist
25
Additional Exercises
Exercise 1.12
Use what you know about audience and purpose to place each of the genres introduced in this textbook (journal article, scientific poster, and research proposal)
on the following continua.
Exercise 1.13
Skim the poem “Next Slide, Please,” written by Roald Hoffmann, who in 1981
shared the Nobel Prize in Chemistry with Kenichi Fukui. In this poem, Hoffmann
pokes fun at seminar presentations. The poem serves as an example of a genre
that differs in many ways from the scientific papers written by this world-renowned chemist.
a. Who is Hoffmann’s audience?
b. What was his purpose for writing this poem?
c. Although you may not have read many of Hoffmann’s scientific papers,
speculate on ways in which this poem is different in organization, writing
conventions, grammar and mechanics, and science content from the many
journal articles that he has written for expert audiences.
Next Slide, Please
there was no question that the reaction worked
but transient colors were seen
in the slurry of sodium methoxide in dichloromethane
and we got a whole lot of products
for which we can’t sort out the kinetics
26
Writing Modules
the next slide will show
the most important part
very rapidly
within two minutes
and I forgot to say on further warming
we get in fact the ketone
you can’t read it on the slides
but I refer to the structure you saw before
the low temperature infrared spectrum
as I say
gives very direct evidence
so does the NMR
we calculated it
throwing away the geminal coupling
which is of course wrong
there’s a difference of 0.9 parts per million
and it is a singlet
and sharp
which means two things
either
you’re doing the NMR in excess methoxide
and it’s exchanging
or
I would hazard a guess
that certainly in these nucleophilic conditions
there could well be
an alternative path
to the enone you see there
it’s difficult to see
you could monitor this quite well in the infrared
I’m sorry in the NMR
my time is up I see
well this is a brief summary of our work
not all of which
I’ve had time to go into
in as much detail as I wanted
today.
(Hoffmann, 1987: pp 51–52)
Exercise 1.14
Science writers, working for magazines such as Science News and Popular Science,
translate discoveries reported in journal articles (written for expert audiences)
Learning to Write Like a Chemist
27
into articles that a more general audience can understand. Consider the following example, where we juxtapose an original passage from Nature with its
translation in Science News. Both passages explore why staggered ethane is more
stable than its eclipsed conformer. You may have learned in organic chemistry
that the eclipsed conformation is higher in energy because of steric (crowding)
effects, but computational results suggest that the real reason has to do with
hyperconjugation.
a. Read and compare the titles of the Nature and Science News articles. What
difference(s) do you notice?
From Nature: Hyperconjugation Not Steric Repulsion Leads to the Staggered
Structure of Ethane
From Science News: Molecular Chemistry Takes a New Twist
b. Now read and compare the two passages below. Identify at least three differences in the writing styles for the two audiences.
This structural preference is usually attributed to steric effects.1–7 . . . Here, we
report . . . that ethane’s staggered conformation is the result of . . . hyperconjugation. (From Pophristic and Goodman, 2001)
Textbooks . . . pin it on so-called steric effects . . . but . . . Pophristic looked
at the other known influence on ethane’s twisting—a quantum
mechanical effect known as hyperconjugation. “The electrons of one
methyl group jump over to the other methyl group,” says Goodman.
(From Gorman, 2001)
c. Select a concept that most chemistry majors are familiar with but that
the general public is not (e.g., the resonance structures of benzene or the
molecular shape of water). Write an explanation of the concept for a general
audience.
Exercise 1.15
Below are five examples of a genre that you are likely familiar with, the
Acknowledgments section. Acknowledgments are commonly included as a
short section at the end of journal articles, just before the References section.
Using the joke and used-car ad examples in this chapter as guides, conduct
a full analysis of the genre of these Acknowledgments sections, using the five
examples as representative samples of the genre. Specifically, identify the
following:
a. The intended audience and purpose of the genre (consider level of detail,
formality, conciseness, and word choice)
b. The writing conventions of the genre (e.g., abbreviations and acronyms, verb
tense, voice)
28
Writing Modules
c. The ways in which the content is communicated in the genre (topic, text,
graphics)
d. The fine organizational structure of the genre. Do this by proposing a move
structure (similar to figures 1.3 and 1.4) for the genre (not the individual
acknowledgments). Assign move labels that reveal the actions taken by the
writers. (Hint: There are some optional moves, i.e., moves that do not appear
in all examples; be sure to indicate which moves are optional in your move
structure.) Arrange the boxes so that they reflect the typical organization of
journal-article Acknowledgments sections.
■
(From Prevedouros et al., 2004) We are grateful to the UK Department of
the Environment, Food and Rural Affairs (DEFRA) Air Quality Division
for financial support. We also wish to thank Anna Palm of the Swedish
Environmental Research Institute and Dr. Knut Breivik of the Norwegian
Institute for Air Research (NILU) for their helpful comments.
■
(From Huange et al., 2004) We gratefully acknowledge the support from
the National Nature Science Foundation of China (20375005) and the
Bilateral Scientific and Technological Cooperation Flanders BelgiumChina (011S0503).
■
(From Raczyńska and Darowska, 2004) E.D.R. and M.D. (SGGW) thank
the Polish State Committee, the Conseil Général des Alpes Maritimes,
and the French Ministry of Higher Education and Research for fi nancial support and the Warsaw Agricultural University for the leave of
absence. I.D. was fi nancially supported by the U.S. DOEOBER Low Dose
Radiation Research Program. Ab initio calculations were carried out at the
Interdisciplinary Center for Molecular Modeling (ICM, Warsaw).
■
(From Dick and McGown, 2004) This work was supported by the National
Institutes of Health (Grant 1R03 AG21742–01).
■
(From Vitòria et al., 2004) This study has been financed by CICYT Project
REN2002–04288-C02–02 of the Spanish Government and partially by
SGR01–00073 of the Catalonian Government. We would like to thank the
Serveis Cientificotècnics of the University of Barcelona (Spain).
Exercise 1.16
Access the homepage for Chemical and Engineering News (C&EN) through the ACS
Web site. On the C&EN homepage, find and select the last issue of the previous year, which will have a cover story titled “(Year) Chemistry Year in Review.”
Open the cover story and read several of the chemistry highlights. Describe the
intended audience and purpose of these highlights.
Learning to Write Like a Chemist
29
Exercise 1.17
Reflect on what you have learned from this chapter. Select one of the reflection
tasks below, and write a thoughtful and thorough response:
a. Reflect on the idea of audience in scientific writing.
■
■
■
What did you know about audience before reading this chapter? Where
did you learn it?
What audiences have you written for in the past? What types of writing
did you do for these audiences (e.g., lab reports, journal articles)?
Have you written for an expert audience before? What challenges do you
think you’ll encounter writing for an expert audience?
b. Reflect on the relationship between reading and writing in chemistry genres.
■
■
■
How might your writing improve by reading authentic examples of chemical writing (e.g., journal articles, posters, research proposals)?
How might your reading improve by learning to write in professional
genres of chemistry?
What aspects of your reading and writing do you hope will improve?
Why?
c. Reflect on the value of genre analysis activities and their role in the readanalyze-write approach to writing.
■
■
■
What are you likely to learn from engaging in genre analysis activities?
How might your reading and writing abilities improve as a result of genre
analysis?
Which focal points of genre analysis (audience and purpose, organization,
writing conventions, grammar and mechanics, and/or science content)
do you think will be most useful to you when you attempt to write for an
expert audience? Why?
d. Reflect on the value of move structures.
■
■
■
30
What is the value of depicting the fine organization of chemistry genres
through move structures?
How might move structures help you with your writing?
Why might chemical writing be structured in such formulaic ways?
Writing Modules
Module 1
The Journal Article
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2
Overview of the Journal Article
An author should recognize that journal space is a precious
resource created at considerable cost. An author therefore
has an obligation to use it wisely and economically.
—American Chemical Society, Ethical Guidelines to Publication in
Chemical Research (https://paragon.acs.org)
This chapter introduces the journal article module (comprising chapters 2–7).
The chapter describes some of the defining characteristics of a journal article
while emphasizing concise writing and organization. By the end of this chapter,
you should be able to do the following:
■
Recognize the importance of concise writing
■
Identify the broad organizational structure of journal articles
■
Explain what is meant by targeted reading and keywords
As you move through the chapter, you will begin to plan your own journal-quality
paper. The Writing on Your Own tasks throughout the chapter will guide you in
this process:
2A Get started
2B Select your topic
2C Conduct a literature search
2D Find additional resources
2E Decide on the broad organization of your paper
Module 1 focuses entirely on writing a journal-quality paper, a paper suitable
for submission to a refereed chemistry journal. Refereed journals include only
articles that have made it through a rigorous peer-review process. In this process,
a submitted manuscript is critically reviewed by two or more anonymous reviewers. The reviewers are asked to judge both the scientific merit and writing quality
of the manuscript. Authors are often required to revise their work before it can be
accepted for publication. The entire review process can take six months or longer.
An account of the review process typically appears in the published article, for
example,
Received for review March 9, 2008. Revised manuscript received August 3,
2008. Accepted August 5, 2008.
Once published, the journal article becomes part of the primary literature of
chemistry. The primary literature is a permanent and public record of all scientific works, many of which are refereed journal articles.
Refereed Journals
Refereed journals publish only papers that have gone through a rigorous peer-review
process.
Submitted manuscripts are evaluated by experts (peers) for quality and originality.
Based on the reviewers’ remarks, journal editors decide to accept, accept with revisions, or
reject each submission.
Primary Literature
The primary literature comprises peer-reviewed publications that describe results of
original research. In general, these publications are the first and most authoritative record
of the work.
In this chapter, we take a bird’s eye view of the journal article. We consider the
journal article’s audience and purpose, stress the importance of concise writing
throughout the journal article, and examine the broad organizational structure
of the journal article. In subsequent chapters, we examine sections of the journal
article in more depth.
2A Writing on Your Own: Get Started
As you work through this module (chapters 2–7), you will be writing your own journalquality paper. Your finished paper will be written for an expert audience, be organized
into appropriate sections (title, abstract, Introduction, Methods, Results, and Discussion
sections, and references), and contain at least one table or figure. The final paper must
34
The Journal Article
include experimental data; hence, a review of the literature or a summary of others’ work
will not suffice.
Step-by-step details on how to complete this assignment are provided in subsequent
chapters in this module. In this chapter, you will prepare to write by selecting your topic,
conducting a literature search, and determining the broad IMRD (Introduction, Methods,
Results, Discussion) format for your paper.
Audience and Purpose
The major purpose for writing a chemistry journal article is to share the results of
original research with other chemists. The primary audience for a journal article
is an expert one; readers are typically well educated and highly experienced in the
subfield of chemistry addressed in the article. Because journal articles are written
largely for experts, newcomers to the field (e.g., students or chemists exploring
a new research area) are often frustrated by the advanced level of these articles.
Details are often omitted that the nonexpert reader would find useful. (If you
find yourself in this situation, we recommend that you also consult related works
written for a less sophisticated audience—textbooks, review articles, general science articles—to help you work your way through the journal article.)
Although the bulk of the journal article is written for experts, a few sections are
often accessible to less sophisticated readers. For example, general or summative
remarks in the abstract, Introduction section, and conclusions are often accessible to
a scientific audience, allowing those readers to grasp the key concepts of the work.
Similarly, many chemistry journals include features (e.g., book reviews, editorials,
and news articles) that are written specifically for scientific and general audiences.
Exercise 2.1
Browse through a research article in three different ACS journals: Analytical
Chemistry, Biochemistry, and Environmental Science & Technology and perform the
following tasks:
a. Try to find two or three sentences that are easy to read and understand in
each section of the article (abstract, Introduction, Experimental, Results,
and Discussion). Next, find two or three sentences that are difficult to read
in each section. What differences, if any, do you notice in the readability of
these sections? Which sections are the easiest to read and understand? Why
do you think some sections are easier to read than others?
b. Read one of your three articles more carefully. What makes the authors
sound like experts? Jot down at least 10 examples of expert-like writing.
Overview of the Journal Article
35
Exercise 2.2
Browse through the Table of Contents of several issues of Analytical Chemistry or
Environmental Science & Technology. In most issues, you will see that, in addition
to research articles, the journal also contains news articles, editorials, features,
and/or book reviews. Glance through the pages of two such items. For each item,
jot down its title and the name of the journal section in which it appears; identify
the intended audience and purpose of the entry.
2B Writing on Your Own: Select Your Topic
Before you can begin to write, you must identify a topic for your paper. When selecting a
topic, keep in mind that your project must be robust enough to result in a journal-quality
paper (not a literature review). Minimally, you should be able to (1) introduce your topic,
(2) provide background information about your topic, (3) describe the methods used to
investigate your topic, (4) present your results (using at least one table or figure), and
(5) discuss your results.
After you have selected a topic, write a two- to three-paragraph description about your
selection. Briefly explain how you will meet the five criteria listed above, including what
data you plan to present. Include a list of three to five keywords related to your topic. You
will use these terms to conduct a literature search.
Conciseness
I find that there is nothing more tedious than papers that go on and on,
with no obvious point.
—Richard Malkin, University of California–Berkeley
Vigorous writing is concise. A sentence should contain no unnecessary
words, a paragraph no unnecessary sentences, for the same reason
that a drawing should have no unnecessary lines and a machine no
unnecessary parts.
—William Strunk, Jr., Elements of Style
Recall from table 1.1 that audience and purpose are communicated through four
subcomponents (conciseness, level of detail, level of formality, and word choice).
The first of these, conciseness, is a hallmark of writing in chemistry. Chemistry
readers (experts and nonexperts alike) want crisp, clean sentences that say what
needs to be said and no more. They do not want to be bogged down in words
that fail to advance or, worse, confuse meaning. Because concise writing is
36
The Journal Article
important in every section of the journal article, we address it here, in chapter 2,
as well as throughout this module.
Novice writers often equate wordy writing with expert writing. They adapt a
wordy and pretentious writing style because (1) they want to make their papers
longer (not at all a goal in scientific writing!) and (2) they want to sound more professional. However, most professionals (particularly scientists) prefer a more concise, direct style. As an example, scientists at a conference of the British Ecological
Society were asked to read two texts that presented the same information, although
one text was considerably wordier than the other (Turk, 1978). On the whole, the
scientists rated the concise version as being easier to read and more appropriate
than the wordy version. The scientists also asserted that the more concise author
was more objective, had a more organized mind, and inspired more confidence
in the work. Thus, wordy language, rather than making you sound more professional, can obscure your message and discredit your objectivity.
Wordiness
The ACS Style Guide recommends that the following phrases be omitted from papers
because they are vacuous and contribute to wordiness:
■
As already stated
■
It has been found that
■
It has long been known that
■
It is interesting to note that
■
It is worth mentioning at this point
■
It may be said that
■
It was demonstrated that
The ability to write concisely is a coveted skill among chemists and an important step toward sounding like an expert. The key is to say only what needs to be
said, deleting unnecessary words (i.e., words that add little substance, state the
obvious, or can be inferred by other words in the sentence). For example, compare the following two sentences. The wordy sentence contains so many unnecessary words that the authors’ message is nearly lost.
In a paper published by Bonderic et al.,2 experiments were
described that led to similar results.
Concise Bonderic et al.2 reported similar results.
Wordy
(It is clear to the reader that Bonderic et al. published a paper because of the in-line
citation. It is also obvious that “experiments were described” in that paper.)
Overview of the Journal Article
37
Sound Like an Expert
Learning to write concisely will help you sound like an expert. This skill requires that you
delete words, as you revise and edit your work, that add little substance or state the
obvious.
Exercise 2.3
Read the following wordy passage (adapted from Liu et al., 2001) and identify five words and/or phrases that could be deleted to make the passage more
concise:
After the mixture had been dried, the remaining residue (CD-capped gold nanoparticles
+ compound 5) was found to express insolubility in dry CHCl3 but the solubility was
restored when water was used in the equilibration of the chloroform. In our judgment,
this finding clearly makes it apparent that there must be some water necessary for the
efficient phase transfer of the nanoparticles into CHCl3. This fi nding leads to the conclusion that the idealized structure that has been proposed for the nanoparticles after they
have been transferred to the chloroform phase (Scheme 2) has some aspects that must
be similar to the structure of reverse micelles. We come to the conclusion that these
nanoparticle-centered assemblies are similar in a conceptual way to gold-filled reverse
micelles. (124 words)
Removing Unnecessary Words
There are several ways to make the adapted passage in exercise 2.3 more concise.
One technique is to replace a group of words with a single word that has the same
meaning. For example,
Wordy
This finding makes it apparent that . . . (6 words)
More concise This finding demonstrates that . . . (4 words)
Wordy
We come to the conclusion that . . . (6 words)
More Concise We conclude that . . . (3 words)
Contractions
Even though contractions seem to make writing more concise, do not use them in your
papers; contractions are not appropriate in an academic style.
38
The Journal Article
Table 2.1 Suggestions for concise writing (adapted from The ACS
Style Guide: Coghill and Garson, 2006, pp 54–55).
Wordy Phrase
Concise Alternative
a number of
many, several
based on the fact that
because
by means of
by
despite the fact that
although
due to the fact that
because
if it is assumed that
if
in order to
to
in spite of the fact that
although
is/are known to be
is/are
it is clear that
clearly
reported in the literature
reported
subsequent to
after
The ACS Style Guide provides many useful tips for converting wordy multipleword phrases into more concise alternatives (see table 2.1 for a few examples).
Concise Writing
See appendix A.
Exercise 2.4
Consider the suggestions for conciseness in table 2.1. Revise these passages by
substituting the italicized phrases with more concise alternatives:
a. Despite the fact that the Lewis acid behavior of group 13 halides has been
extensively studied,8 the Lewis acid behavior of group 12 halides has not.9
(Adapted from Borovik et al., 2001)
b. In order to explain this shift, they proposed that the smaller particles are more
sensitive to UV curing based on the fact that their relative surface areas are
larger. (Adapted from Bol and Meijerink, 2001)
Another way to be concise is to eliminate words that are redundant or that provide information the reader can assume. For example, the phrase “In our judgment” (at the beginning of the second sentence of the passage in exercise 2.3) can
Overview of the Journal Article
39
be removed because the reader can assume that the conclusions being drawn are
based on the researchers’ judgments:
Wordy
More Concise
In our judgment, this finding clearly demonstrates . . .
(7 words)
This finding clearly demonstrates . . . (4 words)
(Some would argue that the word “clearly” could also be eliminated, but the word
was included in the original article and is a favorite among chemists.)
Conciseness can also be achieved through the use of parentheses, as a way to
eliminate information that is superfluous:
Wordy
The results, as illustrated in Table 3, suggest that . . .
(9 words)
More Concise The results (Table 3) suggest that . . . (6 words)
Wordy
The ethanol (research grade and purchased from
Sigma-Aldrich, located in Milwaukee, Wisconsin) was
added . . . (14 words)
More Concise The ethanol (research grade, Sigma-Aldrich, Milwaukee, WI)
was added . . . (9 words)
Exercise 2.5
Revise these sentences. Identify the parts that you consider to be too wordy. Make
those parts more concise or delete them entirely.
Example
The lipid-binding potential was observed to be independent of pH; as a consequence, the results presented in this paper do not support hydrophobic
interactions.
The lipid-binding potential was independent of pH; hence, the results do not
support hydrophobic interactions.
a. Prior to irradiation, the sample chamber was thoroughly flushed with nitrogen, to be sure that air was absent during the irradiation. (Adapted from Bol
and Meijerink, 2001)
b. It is possible that the products of the photochemical reaction that takes place
upon irradiation in the presence of water passivate the surface better than
the photooxidation products obtained during irradiation in dry air. (Adapted
from Bol and Meijerink, 2001)
c. In consequence of this fact, it can be assumed that ArCl+ does not interfere
with the quantification of arsenic in the soil extracts.
40
The Journal Article
d. In a large number of cases, cigarette smoke contributions could not be
determined because the anteisoalkanes and isoalkanes that are used to trace
cigarette smoke particles were below detection limits. (Adapted from Schauer
et al., 2002)
e. Levels of all aldehydes increased during storage compared to the control
sample, as exhibited in Figure 2. (Adapted from Vesely et al., 2003)
f. All of the chemicals were research grade, and they were all purchased from
Fisher, which is located in Pittsburgh, PA.
Using Nominalizations
Another technique employed by chemists to achieve conciseness is to use nominalizations. Nominalizations are nouns that are formed from other parts of
speech, usually by adding such endings as -tion, -sion, -ment, -ity, -sis, and -ence.
For example,
solubility (noun, from the adjective soluble)
distillation (noun, from the verb distill)
Nominalizations often allow several words to be summarized in a single word.
Without a nominalization After we distilled the product, it was a colorless
liquid. (10 words)
With a nominalization
After distillation, the product was a colorless
liquid. (8 words)
By using a nominalization in this last example, we could also remove the word
“we” from the sentence, making it sound more objective. Table 2.2 lists common
nominalizations used in chemistry journal articles.
Table 2.2 Common nominalizations used in chemistry writing.a
absorption
addition
agreement
calculation
activation
aggregation
analysis
comparison
concentration
emission
luminescence
reaction
conductivity
excitation
measurement
reactivity
conversion
extraction
oxidation
reduction
dependence
formation
preparation
synthesis
diffusion
intensity
presence
treatment
efficiency
interaction
purification
a. Nominalizations determined through a computer-based search of 200 chemistry journal articles.
Overview of the Journal Article
41
Nominalization
A noun formed from a verb or an adjective, usually by adding a word ending (e.g., -tion,
-ment). For example,
Extraction (noun, from the verb extract)
Efficiency (noun, from the adjective efficient)
Nominalizations often result in more concise writing. (See appendix A.)
Keep words that convey important content; delete words with little substance.
Exercise 2.6
Consider these sentences taken from original sources in the chemistry literature.
Identify instances of the common nominalizations listed in table 2.2.
Example
Potential conversion of the N1 adduct to its N6 derivative was made possible
through a Dimroth rearrangement, although the efficiency of this process is
highly dependent on reaction conditions and adduct structure (Scheme 2).26
(From Veldhuyzen et al., 2001)
a. The electronic spectra and structure of these systems clearly relate to the
presence of closed-shell metal-metal bonding,8,9 exciplex formation,10 electron
transfer,11 energy transfer,12–14 and chemical reactivity.15 (From RawashdehOmary et al., 2001)
b. The excitation spectra were corrected for the beam intensity variation in the
Xe light-source used. (From Dhanaraj et al., 2001)
c. We have reported the preparation and characterization of deoxyuridine
nucleosides and nucleotides where ferrocene was conjugated to the nucleobase through unsaturated bonds5 and the preparation of adenosine and
cytidine modified with ferrocene at the 2′-position through butoxy linkers.6
(From Yu et al., 2001)
d. The relative intensity of this signal permits a comparison of the strength
of the interaction between oxides in dependence on the preparation conditions (milling time, calcination temperature and time, presence or absence of
water). (From Spengler et al., 2001)
42
The Journal Article
Exercise 2.7
Try rewriting example sentence (d) in exercise 2.6 without using any nominalizations. How does your revision compare to the original in terms of conciseness
and clarity?
Nominalizations usually make writing more concise. One important exception,
however, is using nominalizations with forms of the verb do (i.e., did or was done).
In such cases, nominalizations can make the sentence wordier and should be
avoided. Consider the following examples:
Wordy Komiyama et al.2 did an analysis . . .
Concise Komiyama et al.2 analyzed . . .
Wordy A synthesis was done by Martinez et al.7 . . .
Concise Martinez et al.7 synthesized . . .
et al.
An abbreviation (for the Latin et alia) that means and others.
It is used when referring to authors of a publication that has three or more authors. The
first author’s last name is listed, followed by et al. (with the period).
Exercise 2.8
Rewrite the following sentences to make them more concise. (Do not delete original citations, indicated by superscript numbers.)
a. At this point in time, there exist only a small number of reported examples of the synthesis of carboranes from eneynes,20 the first of these being
the synthesis of 1-isopropenylcarborane.21 (Adapted from Valliant et al.,
2002)
b. Table 1 accurately summarizes the reaction products from the two reactions that were performed: the hydrogenation reaction and the oxidation
reaction.
c. Polyadducts of C60 with well-defined three-dimensional structures are
of great importance, based on the fact that they possess interesting
biological1a and material properties.1b,c (Adapted from Mas-Torrent et al.,
2002)
Overview of the Journal Article
43
Exercise 2.9
Consider the various ways in which you can make your writing more concise.
Return to the wordy passage in exercise 2.3. Revise the passage so that it is more
concise. As a guideline, consider that the original was only 90 words long!
2C Writing on Your Own: Conduct a Literature Search
In Writing on Your Own task 2B, you generated a list of three to five keywords related to
your paper topic. Use these keywords to search for peer-reviewed journal articles about
your topic. The goal is to find at least four articles relevant to your research area. Search
scientific databases such as American Chemical Society Publications or ScienceDirect; be
cautious with general Internet search engines, such as Google, because they do not limit
searches to the primary literature.
When you find an article of potential relevance, read the title, abstract, and keywords. If
this information appears relevant, skim the rest of the article (including tables and figures).
Take notes on (1) what the study was about, (2) what methods were used, and (3) what
conclusions were drawn.
Print out each article that you decide to use. Be sure to print the entire article. A common mistake is to print the text but not the references. Check to be sure the printout
includes full bibliographic information (i.e., the full and abbreviated journal name and the
article’s title, authors, volume, year, and inclusive page numbers). For a Web-based article,
write down the full Web address and the month and year that you accessed the site.
Keywords
Keywords can be used to search for articles in your field. Most journals require authors to
include a list of keywords with their submissions. Oftentimes, the words are selected from a
master list provided by the journal.
Organization
In chapter 1, we learned that genres have both broad and fi ne organizational
structures. In this chapter, we focus on the broad organizational structure of the
journal article, signaled by identifiable sections and headings. In general, journal
articles are divided into four major sections. These sections have the familiar
names Introduction, Methods, Results, and Discussion; collectively, this organizational structure is referred to as the IMRD format. In addition to these four
44
The Journal Article
major divisions, journal articles also include a title, abstract, references, and often
acknowledgments. (Acknowledgments are required for works supported by a
funding agency; otherwise, this section is optional.) On occasion, journal articles
also include a section for conclusions, but more often conclusions are included at
the end of the Discussion section. Chapters 3–7 go into detail about all of these
sections; in this chapter, we briefly highlight the IMRD sections.
IMRD Format
The typical broad organization of a journal article:
Introduction
Methods (or Experimental)
Results
Discussion
The Introduction section of a journal article identifies the research area,
explains the importance of the research, provides background information, cites
and summarizes key literature in the field, points out what still needs to be studied, and introduces the reader to the work presented in the article. The Methods
section—formally known as Materials and Methods or Experimental (Section)—
describes how the study was conducted. The Results section summarizes quantitative (and possibly qualitative) data collected during the study. In the Discussion
section, authors interpret their data and suggest the larger implications and/or
applications of their results. Each of these major sections can be further divided
into moves, as we will see in subsequent chapters.
In recent years, variations have appeared in the traditional IMRD format. For
example, some journals include explicit headings for all four divisions, some use
fewer than four explicit headings, and some use no headings at all. The sequencing of the headings also varies. For example, The Journal of Organic Chemistry typically places the Experimental Section at the end of the article, while the Journal
of the American Chemical Society places the Experimental Section in a footnote.
Interestingly, in the past, chemists were discouraged from combining the Results
section (presentation of data) with the Discussion section (interpretation of data),
yet today a combined Results and Discussion section is commonplace. For the
journal article that you write in this module, we recommend the traditional
IMRD format. However, if you are submitting a paper to a journal for publication,
you should follow the organizational structure recommended or required by that
journal. Because every journal has slightly different requirements, it is important
to read the “Information for Authors” for the particular journal to which you plan
to submit your paper.
Overview of the Journal Article
45
“Information for Authors”
A set of journal-specific instructions for hopeful authors that includes the following:
length specifications
section requirements
appropriate research areas
Exercise 2.10
Browse through The Journal of Organic Chemistry, Journal of the American Chemical
Society, and Organic Letters. What variations in sectional divisions do you see? Are
all headings shown explicitly? Repeat this exercise with two or three non-ACS
chemistry journals (e.g., Applied Surface Science, Chemical Physics, and Journal of
Chromatography A, all published by Elsevier).
Hourglass Structure
The IMRD format creates what is sometimes called the hourglass structure, a
feature common to journal articles across many fields of academic research. The
hourglass depicts the way in which the scope or specificity of the paper changes
throughout its sections, as shown in figure 2.1. The Introduction section begins
with a broad overview of the research area but narrows as the authors mention
specifics about their presented work. This specificity is maintained throughout the Methods and Results sections and then broadens again at the end of
the Discussion, where research findings are described in a broader context. An
Figure 2.1 The hourglass structure of the
IMRD format (adapted from Hill et al.,
1982).
46
The Journal Article
hourglass icon is used throughout the textbook to remind you where you are in
the hourglass structure.
Hourglass Icon
The hourglass icon is used in modules 1 and 2 as a visual reminder of the level of
detail required at different points in your written work.
Exercise 2.11
Browse through three articles in Chemical Research in Toxicology or the Journal
of Agricultural and Food Chemistry. For each article, copy and paste into a text
document one sentence from each IMRD section that is consistent with the hourglass structure. Examine each group of four sentences. Is the hourglass structure
apparent in these four sentences? Explain.
2D Writing on Your Own: Find Additional Resources
Use the articles that you found in Writing on Your Own task 2C to locate additional
resources, as follows:
1. Begin with the most recently published articles. Browse through their reference lists to
find additional sources that you may have missed in your literature search.
2. Read the Introduction sections of your articles. Because Introductions provide relevant
background information and cite others’ works, a targeted reading of the Introduction
can help you identify commonly cited sources in your field (a technique known as
footnote chasing).
3. Go to the library and/or the Web to obtain copies of these additional resources.
4. Read, sort, and code your articles by topic, methods, and/or results.
Targeted Reading
Before ending this chapter, one more purpose of the IMRD format is worth noting:
the IMRD structure promotes targeted reading, allowing readers to locate science
content in an expedient manner. You might be surprised to learn that chemists
do not typically read every word of every article from start to finish. Rather, most
chemists read selectively, targeting sections most pertinent to their interests. For
example, most chemists glance first at an article’s title, abstract, and keywords.
Overview of the Journal Article
47
This cursory glance is often enough to decide if the article is sufficiently relevant
to merit a closer look. If the content appears promising, they next target a specific
section of the article. For example, a chemist interested in planning a synthesis
will read the Methods section; a reader wanting to learn more about potential
uses of a novel compound will read the Introduction and Discussion sections.
Less relevant sections of the article are skimmed or skipped entirely. Only a few
articles, those most pertinent to the reader’s interests, will be read in their entirety
(and then usually many times).
Targeted Reading
Students are generally accustomed to reading texts from start to finish, with the intent of
understanding everything. You may have read a textbook chapter in this manner.
Scientists rarely read research articles like this. Generally, scientists target a given section
to look for specific information. For example, a chemist might target the Methods section
for the sole purpose of finding out what brand of instrument was used.
The IMRD format, together with the finer organizational structure (moves) and
language of the journal article, helps readers quickly locate the content that they
seek. As a developing writer, it is important that you learn to present your content
in these expected ways and places. As readers scan your paper, they should be
able to quickly locate your topic, the nature of your work, the methods you used,
and your conclusions. The use of keywords in your title and abstract and throughout the body of your paper is especially important. Because so many scientists
now turn to computer-based technologies and search engines to find pertinent
and current information, if you fail to use expected keywords, your work may be
missed even if relevant.
Exercise 2.12
Browse through three research articles in an ACS journal of your choice. With
only a cursory glance at the title, abstract, and the IMRD sections, determine the
topic of research, the methods used, and a brief summary of the conclusions.
(Note: You should be able to identify the topic and methods, even if you do not
understand them.)
2E Writing on Your Own: Decide on the Broad Organization of Your Paper
When you actually finish your journal article writing assignment, your paper will be
written in either the IMRD format or a format specified by a particular journal. If you are
48
The Journal Article
writing your paper for publication, you must select the journal to which you will submit
your manuscript and follow its submission guidelines (which may require a modified
format). Most scientific journals (including most ACS journals) post their submission
guidelines on their Web pages. In general, submission guidelines describe the type(s) of
articles that the journal considers for publication and specify how manuscripts should
be organized and formatted. For most ACS journals, you can also download a template
to be used in your word-processing software that will help you follow the journal’s
specifications.
Decide on the broad organization of your paper. Will you follow the traditional IMRD
format? Or will you follow a modified format specified by a particular journal?
Recall that the actual sequencing of sections in a completed journal article does not
normally reflect the exact order in which most authors write their articles. In fact, writers often begin with the Methods section (as you will). As writers progress through the
different sections of their papers, they go back and forth among the sections, revisiting
previously drafted sections to modify them as needed.
Chapter Review
As a self-test of what you’ve learned in this chapter, define each of the following
terms for a friend or colleague who is new to the field:
conciseness
et al.
hourglass icon
hourglass structure
IMRD format
Information for Authors
keywords
nominalization
primary literature
refereed journal article
submission guidelines
targeted reading
Also, explain the following to a friend or colleague who has not yet given much
thought to writing a journal article:
■
Main purpose of a journal article
■
Audience of a journal article
■
Broad organizational structure of a typical journal article and
its variations
■
Purpose(s) of each section (IMRD) of a journal article
■
Importance of concise writing
■
Techniques for writing more concisely
■
Resources that can be found on a journal’s Web site that can assist writers
who want to prepare a paper for that journal
Overview of the Journal Article
49
Additional Exercises
Exercise 2.13
Think about the purpose of each section in a journal article. For each of the
sentences below, decide which section of a journal article (I, M, R, or D) it comes
from and explain what led you to make your decision:
Example
When 13 and 17 were sialylated on a larger scale (2.0 and 3.5 mg, respectively)
glycopeptides 20 and 21 could be isolated in 94 and 64% yields, respectively,
after purification by reversed-phase HPLC. (From George et al., 2001)
Results. Data (specific numbers) are reported, along with a reminder of
the methods used. The passage does not interpret the data. Therefore, it is
probably not part of a Discussion section.
a. Most epithelial cells produce mucins, that is, glycoproteins in which the
polypeptide backbone consists of highly conserved tandem repeats with
complex carbohydrates linked to multiple serine and threonine residues.1–4
(Adapted from George et al., 2001)
b. Studies directed toward chemoenzymatic synthesis of more complex mucinderived glycopeptides, as well as attempts to use the glycopeptides described
herein for development of cancer vaccines, are underway in our laboratories.
(From George et al., 2001)
c. Tetrahydrofuran and diethyl ether were dried using sodium metal and then
distilled, as required, from sodium benzophenone ketyl. (From Banwell and
McRae, 2001)
d. Connectivities were observed between these protons and both C2 and C6 of
dA. (From Veldhuyzen et al., 2001)
e. All aqueous solutions were made with water purified by standard filtration to
yield a resistivity of 18.0 MΩ. (From Veldhuyzen et al., 2001)
f. Most every heteroatom of DNA exhibits at least some nucleophilic character,
and each may be variably targeted for alkylation depending on the nature of
the electrophile and the reaction conditions. (From Veldhuyzen et al., 2001)
g. Instead, it may have formed insoluble dimers, trimers, and higher-molecularweight species as previously described for related structures.39,40 (Adapted
from Veldhuyzen et al., 2001)
h. This work has shown that CD-capped gold nanoparticles with average core
diameters of ca. 3 nm act as effective hosts for cationic ferrocene derivatives,
as evidenced by electrochemical and 1H NMR spectroscopic data. (From Liu
et al., 2001)
50
The Journal Article
i. The fast development of methods for the preparation of metal and
semiconductor nanoparticles capped with organic monolayers is opening
interesting possibilities for the functionalization of their surfaces.1 (From Liu
et al., 2001)
Exercise 2.14
Familiarize yourself with the article by Boesten et al. (2001) about the Strecker
reaction that appears at the end of this chapter. Look over the article as a professional chemist would to simply orient yourself to the article. Follow the steps
below:
a. Read the title.
b. Read over the abstract. (This article does not include keywords.)
c. Skim the first sentences of most paragraphs.
d. Look over the tables and figures.
e. Answer these questions.
1. What was the study about?
2. What methods were used?
3. What conclusions were drawn?
f. The Strecker synthesis article does not include section headings; however, it
loosely follows the traditional IMRD format. Reread the article and indicate
where each of the section headings could be placed. What difficulties did you
encounter in placing the Results and Discussion headings?
Exercise 2.15
Compare the changes that you made for exercise 2.9 with the original Liu et
al. (2001) passage below. Were you able to shorten the passage to the 90 words
achieved by the authors? To what extent was the original meaning of the passage
preserved in your version?
After drying, the residue (CD-capped gold nanoparticles + compound 5) was found to
be insoluble in dry CHCl3, but the solubility was restored when the chloroform was
equilibrated with water. This fi nding clearly demonstrates that some water is necessary
for the efficient phase transfer of the nanoparticles into CHCl3. Thus, the proposed idealized structure of the nanoparticles after their transfer to the chloroform phase (Scheme
2) has some similarities with the structure of reverse micelles. We conclude that these
nanoparticle-centered assemblies are conceptually similar to gold-filled reverse micelles.
(90 words)
Overview of the Journal Article
51
Exercise 2.16
Revise the following sentences so that they are more concise (and more professional). If you need some help, consult the “Audience and Purpose” section above
and the “Concise Writing” language tip in appendix A.
a. The energies of the associated LMCT transitions would be above the energy
range that would appear to be accessible here (as shown in Table 6); as a
consequence of this fact, all of the transitions that have been observed must
be due to the axial (z-polarization) or equatorial (y-polarization) tyrosinates.
(Adapted from Davis et al., 2002)
b. The present results are in agreement with the results that have been obtained
from other spectroscopic studies that have been conducted on n-alkyl modified stationary phases.27 (Adapted from Singh et al., 2002)
c. The reaction mixture was stirred for 1 h while allowing it to reach room
temperature during that time.
Exercise 2.17
Reflect on what you have learned from this chapter. Select one of these reflection
tasks and write a thoughtful and thorough response:
a. Reflect on the level of professionalism in published journal articles.
■
■
What are the predominant characteristics of published journal articles
that make them appear so professional?
What aspects of this professional writing will you try to emulate?
b. Reflect on your own writing abilities.
■
■
■
What aspects of your writing will you need to improve to move toward
more professional writing?
How will you go about making these improvements?
What do you think will be most challenging about learning to write for
expert audiences?
c. Reflect on your reading habits.
■
52
Based on what you’ve learned in this chapter, how might you change the
way in which you approach journal articles in the future to improve (1)
your understanding of the articles and (2) your writing abilities?
The Journal Article
Asymmetric Strecker Synthesis of
a-Amino Acids via a
Crystallization-Induced Asymmetric
Transformation Using (R)-Phenylglycine
Amide as Chiral Auxiliary
Wilhelmus H. J. Boesten,' Jean-Paul G. Seerden,' Ben de Lange,*-'
Hubertus J. A, Dielemans,' Henk L M, Elsenberg.t Bernard Kaptein,*
Harold M. Moody,' Richard M. Kellogg,' and Quirinus B. Broxterman*''
/J.S^/ Rcwtirch Lifa ^cit.'nct.'^-Orgdtik: (*ht.'ini*lrv and i.SifiwKtity^i*. P.O. Max IX.
61fiO :\[1) < wlwii.. ottfl Svii(.:i>ttt tt. I., kdclijk j. 9747 . [7 (rfoiiiugwi, '1 he \clh<nifiti<k
rimt\.hr{>x{wnifin (1 (knl-pronp.corn
Received December 22, 2000 iHevised Msaaaien Hsce.vsd ,',fa;cft fi. 200)',
Diastereose I active Strecker reactions based on (f?)-phenylglycine amide as chiral auxiliary are reported. The Strecker reaction is accompanied
by an in situ cryslalli is lion-induced s symmetric Iran storms lion, whereby one disste reamer selectively precipitates snd csn be isolated in
76-93% yield and dr > 99/1. The diastereomerically pure a-a mi no nitrite obtained from pivaldehyde [R! = t-Bu, Rj = H) was converted in three
steps to (S)-rerMeucine in 73% yield and >98% ee.
The as> ininclric sy ill he sis of cx-iiiiiino acids and dcrinilivcs
is ;in iniponiiiit topic ;is ;i result of their cxlcush'c use iu
ptiiirmacculiails and agroclicmiciils and as chiral ligaiids.
Many highly citmtiosdcclivc appraadres have been reported.' Industrial prodiielion of a-amiuo acids i-ia the
Slicckcr reaction is historically one of [he most \orsalilc
methods to oblain llicsc coni|X>unds in a cost-effective
manner, makiiig1 use of inexpensive and easily accessible
' I)S\[ KesL'iiivll l.i(eSL-ii:riL-i:s-<h!siiiii:l.'liL'rilnln S: lik^iiliilisis. E:-iliiiil
lov Itii d^ l.iniiiL': l!un-ll.l.;iiisK-ilJ"Bds!H-!;™iip.i:o[]i.
Sjii.-oni n.V.
(D'l.ajfaliiKs. M.:IJautii>. .l..ijjjjii(..-J t nA ID'J'J. .'(5. 21?. i.l'J talivicla.
C.i l)iu-ilL>-\'illL»;is. M. I). rnrutHttnm: .J.v.r ,'ni IVVX v. .1517 (ol
\ViIlinms. ]( \[. Xj-nItif ii.< ,il'IIplim,'.'V .• ia;,;• u-.-\:uia; .• i , I i / f . KTS;:Iiti.ni•
(Isliwd. 1'JS'J
1C.'5?1.-olC;/S4iC f:Kf: Sj;.03
Published on Web 03y30f2001
starting male rial 5.: The Slreckcr rciidion is usually followed
by resolution of the raccinic ammo acid or aniino acid amide
obtained after hydrolysis of the amino nilrilc.-5 Rilher process
leads lo ;t maximum yield of 5(1% if the unwanted ciiitiilioincr
15 not raccmi/ed. In principle, asymmetric synthesis np(2) (MJ Kuny. J J . [ji //fj.-r.'V^.'-JiVj1!1: .VfL'f-^AvLVftT.vt- :\,'.'fliL'>/*: UdtiK-hcii.
£i.. riolliiiiiiiii, R. W.. Millar, .1.. Sirhiiiuiiiuin. ]'., F.Js •. Tliiniii; \^rl;n':
Smmjin. I'J'J\ 19.11•. Vol. !•'. 21, 11.1 4.4. (h) SlialMii. V. \[.; lialuk-v. V
A.: Mi>km»liin. \'. s. «r,-.« ' 'tieiu. if...- t'JW. A-.1. MS (j) sirj.-lir. A .-inn
( 7j..|ii. ."l.wiii. IS^I). -.'. 27.
(.IJl'ov ]'^^ i^.\y, s^i;: r^y^ln!io]i l>y Lmiiiw)LML]iL[:LS^!i. (LI) Sunk^. ']'.;
Kalinin, ».; IduhUEi. \V. [[ 1; nroxlLniiiin, CJ. ».; SLlioLiiiiikLr. 11. 1..;
Kamijluiif,. J.: J-'.inii^'^i.j. t-'.: 'I'ojiiLil.j. t'.i Rulics. t-'. L'. J. 'J'. ]n .S'IL-I-L'^)vi.vri!v ft.(J1Mii.y.M.: I'iiK-l. H.. l-tt.i IX-VV.-r. Now V«'k. 2001). Chapttr
2. flij k^yoliiLiiMl b\ LI^^LLV^.^. DELHI/.. K.L ^'akliLlLMLii. ]J. ]]1 ;.'>rr.'juf ^ 'L|I(m'.^.-.v
,•«! AK, «h- .<.y« m«i.,-.' \ X-11 • w j iii IK i in. i 'w 5: \ ;>i. i. p w V
R 2V" Arrerran Khsri"6l Strie^
Overview of the Journal Article
53
Tal)k- ]. AsiinrlK-liiu MivtUr KwnliiiilK (>L'l'KH'luai>ld>'a'K: Ainiik I LiilJ l'i\;ilJi'h>Ji; 2
oiurv
savcn!
Kill]) ("(')
lintf 111)
yield f;yj
dr (A'.,SV 3:YA'./i',i 3'
1
2
3
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Mol>ll.:Z I'rOll. I:!)'
Kl'iiHI
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'• ULilak-d \idil alWr cva|n>ra1LLiii ot'Uic ^ilvout (cntiy ] 1 IT liltralimi Lif'tin.vi|iitatL.Ld amimi mink- J (outvie 2 <>). ''"i'lic <1r u^ <k'K'niiiiK'<l by 41 NMK
*;]>LVtro^Mpy. ' Ratio ill ^oiuillk: volume.
proaclics lhal load to a m;i\imum yield of 100% of a single
cnantiomcr arc snore advantageous.
Recently several analytic asymmetric Slrcckcr reactions
leading to N-prolcclccI iiniiiio siilrilcs in high ce's and high
\iclds have been published.1 Alternate eh . diaslcrcosclccli\ c
Strcckcr syntheses using; a broad variety of chir;il inducing
agents, like a-iiryfcihylamincs.' //-aniisio ;ilcolm!s ami derivatives.'' iiinino diols." sis,i>ar derivatives." and sulfinates"
have teen reported to pi'oi'idc Ihc n-aniino tiitrilcs uiih
N'lining diastereoselcclivilics. A major drauback of" these
chii-.il auxiliaries can be cost and/or availability, because they
;ire used in Moiehioiuelric ;iniounls and in principle losl
dnrini; the conversion. Furthermore, in many cases the
nL-iiiuino nilrilcs need to be purified in a separate step lo
obtain dia stereo me rically pure compounds. Pniificalion
requires, for example, ciyslalli/jition or chromatograptiy.
which nuiv lead lo losses. An inlcrcsliiii; solulion lo llicsc
problems would be a cr> si alii MI ion- induced asymmetric
transformation.'"^ in wtiieh one diastereomcr precipitates
and Ihc other cpimeri/cs in solnlion \'ia Ihc corresipondini;
inline. This would lead both lo high yield and high
diaslcrcosc!ccli\il> in a practical one-pot procedure.
Recently, optically pure (/0-pheiiylglycinc amide 1 became
readily accessible as a result of application on an industrial
scale as key inicrmcdiiitc in (he cn/yinalic synthesis ol"
/j-laclani anlibiotics.l: Either iiniinopcptidasc-calaK /.cd hydrohsis of raccmic pltemlglydne amide* or asymmetric
I rans format ion of raccmic phcnylglycine amide \vith (.S'jmanJelie acid as resolvini; agcnl-1 can be used lo prepare 1.
Bccausc of ili rcadi availability on a large scale and its
anticipated easy removal via analytic hi cls'oge no lysis, lie
decided lo investigate lite application of (/0-phcinlglycinc
amide 1 as chinil at^iliary in asymmetric synthcsis.
In (his p;ipcr. the first l\vo examples of the use of (if)plicm lgl> cine amide in asi mmclric Slrccker reactions arc
presented. Pivaldchydc and .1.4-dimclhoxyphetiylaceloiic
liai'e been used as starting materials. H liich lead. respccli\-ch.
lo cnatiliomcrically enriched wMcucinc and (i-niclhyl-do|xi.
two important nonprolcogcnic a-aniino acids for pliannaceulical applicalions. In addition, fm-lcucine has considerable utility as a clural building block.1 •
The asymmelrie Streckcr reaction of (/O-pheiiylglycine
amide 1. pn-aldcliydc 2 and HCN generated in situ from
NaCN and AcOH \vas studied (Table 1). Amino nilriles
(K..S'1-J and <j?,R)-3 were obtained in 80% yield in a ratio of
65:35 by sliiring an cquimolar mixture of 1 (as AcOH sail)
(4)(ii) Sigmiin. M. K.; Viitliiil, I'.: .Fai:olisi;ii, p.. \. .-im;i-i!-. ("f:,™ in!
:•:,!. .'-.jti;,1. 2IMIII. i'J. 1271;. i.Li.i J'niu-r. I. K.. WW-luin. w. (i.: Kimt/. K.
\V.. Snain1"- M- ] • • • lli)Vi:yd;i. A. ii. .,'. . im. iVli-ffl. St. 2INHI. 122. 2S57.
(t) Ishikiiii. II.: Koiiiijiiniii. S.: iliiSL'jjimii. V.. Koliiiyiisln. S...'. . im : Vifm.
Sn-. Hill". :'.v. ?(>2."(ilj Vih-hal. I': JjiMbsiii. I-,. S. («•» l.ai. 2I1IHI. ^.
Sf>7. ^} f>iivv. I-:. J.l (iressaii. M. lira. ;•.«;. im. !. ]?7.
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/O.-144(1 (I)) \\Vifc. !.: \'nlk. i;.-J.L l-rallili. ,\"\V Jt'l'liAni-nJi.- .•\n-inaa-ln2 .','. H.ll.(ij.Uiaristi. L: KMII-KHIIHI. .1. ].-. R;yjs. A.: Uul.inK-. i
Ji-rrn'k'ifr-i!.- A:\KKdry \yy'i ill. 2441. (J) Sjwlman. .1. C.i •|aliiia. A.
(;.-. Kellug!'.. R. M.: Muolsiiiii. A.; JL- IW-r, A.: Iteinslciis. I'. 'I'.: ]!HMII:III.
\V. I'...'. 'J:"». I'lian 1'JS^. f-l. l(l« (ij Nlinil. li \t ;l!l:Kk. t.. \ •. Malk-r.
W. [.. ./ llr/;. i.'lKm. I'JW. .;.•.'. ?.id'J.
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Ma. ]).-. Tiiin. li.: /on. (I. J. (>!;. (Vicui 1'JTO. W, 12(1. (t-j t'lialvaluiny.
'I'. K '. lliissaiii. K. A.'. RiMf, l.i \'. i'i-lnH'infrii:! IM?. .-",', 'J1T>.
(7f W'oins>o«. K.: liiadimaim. il.. S!almi:i-1«;i. i'.. Itudtniikl. 11.: Vi\tl«r.
M.. ImaailJi- II. :.«•:»i;i. ian. c 'I™. l'J»5. 5M>.
(S)Kiin/. li.'. Sasur. W . SJiaii/unlsk-li I).: Dutkcr. M. j'.,vfc,-;;i .•!«-;
C.'ii-:::. 1'J'JI. 64').
(1J) Davis. 1". V : I'aiiL-lli. I). I.. ./. (J:-s. i 7i.:m. 199S. *:. l')K].
(l(J)Oiily ^L-ry IV^^ i;^:L[nplv-s h>l' ^r\*l:]lliH-;LLii>n-mdiiL^tL asy]iiciii;lrK[Taiisf'oiinalmils ill Slr^ckor ivnumns li:i\'o iKvn rop^nlotl l^asotl on aryLalk^l[llL'lliyl kt:l(i]lL's: fa) \Vt:iiL;^*. K.: tivics. K.. Slciinnk'. II.. S^llvailk. W.
t'ln-ii,: ll.-r. 19T7.' ,'.'(/. 2(WS. (I'j W'uiiij.ys. K.: KliM/.. K.-l\: Dnwlt II.
t'ltilll. Her. I'JUII. i1:.-. 7H).
f l i ) ] - \ j r a liroatl Jiscussion ^l^' uAMalh/alHin-LiKkiivJ asy]n[iio[rik:
[Tail^r^[Tllal](iiL. SkiL1: \'k:ikjs. E:.. Clla|)illail. R. ^'.. l.itl. S.: Mallei1. M..
I'mivll. I) it..-', .in Client. .s',it. 2IMII1. iJJ. ?IH? and relVrjnws (liiK-in.
i'l!)lSnissink. A.: ld«is. ]•.. S.: ,k- Vr,i,im. I-:. fJro. ;:JHVM •(« :)c.-.
1WS. .'. 12S.
(1.1) 00 linuslcn. \V H. I l:.iini]iL':in Parml A]5[>l. i;.i' 442^i;4, I'WI
(I'liiin. ANtr. I'W2. i'/'j. -12D(i2r). (hi liiKsljn. W [[ .1. luai'ivan Pak-nl
A|i|>l. !-,!' JJ2-WS. 1'Ml (L'lKin Aiwr. IVI2. ,'iVi: 42(IMs)
(N) l^iiiiniarius. A. S.: SLlmami, M.. S[ini;L. K.: Ktj1L^nli;Llin, M..
Mm I li n ad 11:1-. K ; Draii/. K. '! \:lr,itit:,lr: in: .-'ifymnian- MJ"JS. d. 2K51
1122
%. I ell, Vc:. 3. \o. 3. 2001
54
The Journal Article
u ith 2 ;ind NaCN in McOH ovcrnighl at room temperature,
followed by evaporation of I lie solvenl lenlry I)- The
diaslcrcmncric ralio of (7;..s>3 and f.K.H)-3 was determined
by 'H \MR 011 ihc basis of the relative integration between
I he /-Bn signals ;it 1.05 ppm for (rt.,S>3 and 1.1? ppm for
(/iJO-3- Tht assignments have been made on Ihc basis of
Ilie absolute configuration as established by X-ray analysis
and conversion to (.S'j-to-j-lciicine (\ idc infra).
Because in mclliaiiol cry sla Mi/at ion of aniiuo nil rile 3 did
not take place, firs! Ihc solvent was varied in order I oat tempi
lo find conditions for a cr>slalli/,;il ion-induced asymmetric
I mils formal ion. Ala McOH/2-PiOH ratio of l/Viiniiiio nilrile
(/(..V)-3 was isolated in 51 % yield and dr 9WI (entry 21. Other
comb in;: I ions of alcoholic solvents failed lo lead lo a higher
yield of precipitated (KS)-i in highdr (cttlrics r» and 4). On
further screening of solvents il was observed Ihal upon
addition of I1;O to the inclliauol solulion selective precipitation of aniino nilrile (W..S>3 occurred giving (R..V)-3 and
(R.R)-i in a ralio of SI: IV and fiy% yield (cnln 5). The
asyiinitciric Sticckcr re ac I ion uas funher studied in H O
alone using temperature as a variable. The results of Ihcsc
experiments arc given in Table 1 (cnlrics (i—'}}. After
addilion of KaCN/AcOH at 21-2X "C lo (/O-phciiylglycitte
amide 1 and pivaldchydc 2 in 1I:O. the mixture was heated
lo the mdiealed temperatures.
After approximately 24 h of stirring, ihc mixture nas
cooled to VI "C and the precipilalcd ami no nilrile filtered
and analy/cd by L H NMR lo determine the dr. The results
in Table- I show lhat optimal results were achieved after 24
h of stirring in water at 7(1 C'C. The aniino nilrile (.K.M-3
was obtained in l).n>% yield and a dr -• '•)'•)/1 via a crv'slalli«ilion-itiduccd asy mmetric ifiinsformntion (cnlr) <>). At
lower icmperalures the cpimcri/atiou reaction is slower.'-5
The cryslalli/ation-induccd asymmelric Irons format ion in
water a I 70 'C is verified further by the observed increase
of Ihc dr of (R.X)-i as a function of (he reaction lime (Figure
I). After :>() h Ihc precipitated (/(..s>3 w a s oblaitted uilh a
dr ;- W/l.
Fifiuix- 2. t'rysinilli/iiii[>n-iiiJtLti;d Li^ymiiictrii: 1rLHiKt^rrn;i1iL>n <>!"
:imino nilrilt: 3.
niation can be c.\plaittcd as slioiut in Figure 2. Apparently,
the fv-face addition of CN lo the inlcrnicdiale imine 4 is
preferred at room temperature in incllianol and results in a
dr 6?/fo. Al elevated lempenilures in water the diaslereonici'ic outcome and yield of Ihc process is coturolled b\ (he
reversible rcacliouof the aniino uilrilcsJ to the inlcrnicdiale
iminc and by Ihc difference in solubilities of bolh diaslcrcomcrs under Ihe ;ipplicd conditions. : ''-'~
The absolute configuration of aniino nilrile (KS)-i Mas
confirmed by X-ray analysis as shown in Figure > ls and byconversion lo (.S1) -I? i -/-I cue inc.
Figure 3. X-niy sLriLctiiTLL <jf itniiiio nilrik- iJt.S}-3.
Figure 1. (.•i-vsialli/aiiiw-iinUwi.-d asvniinoliii.- tran^liirmaliun uf
intiino nilnlL' J in n:ncr ill 7f) (.'.
"Ilio observed diastcieoselect^'ilv in the asymmetric Struckcr slcp via ihc cryslaIh/jilion-induced asymmetric iransfor(15) A1 liHifi- li!]H[)i!]-iiuin;s, timor yiflJsol'jii-oiIUL-1 HOI-L' 1'iiind. |in>liiihl>
by 1k.-«r:ntili«n ill' :miiiio iiilrik-
Conversion of the amino nilrile (/(..S>3 lo (.S)-to-)-lcucinc
7 was accomplished via the reaction sequence shown in
Scheme 1. Hydrolysis of («.,S')-3 lo the diamiric (W,.V)-S
(Ki) ]\jr ^\:nil]>]k.L. ill 11 n; L-;iSk; ol']>tSk;il\ I;!k.\:lijclc (]H?1 ilttisli'LilL'itj it hWs
ItHLiiJ lltul in *<ikitii>n 1lic ini[i,ill>- lonTicd niinnr UI'IIKT |i|-i;tcrcrni.ill>tnVL'ipilHilv.L<l iiiulci- L'|->MLil)i^n1LLin ..Miulili^nv
f 17) ]-'or LI t1i^L•Ll^^i^)[l kit' iLsyrimivririk1 1ransl'i)]1llrLlioil orct-LilllirM [lil|-ikLs
uilii miiiiik-lii; ;iLii], sou: ILiss'aii. \. i ; liiiyur. !•'.•. .liifliims. .1. C .:'. !'iu
.V'\-.. }'crl:;n '/ran*. .' TWS. .^7-17
i'l^VL1ikror>^ljil ^tRU-aurk1 <>l (.''^.-^.J ln^hccn itk']n^Ltv.LJ ML tlio t'jimhi-di;o
tn]ASL:itlu;;!-;Lf)tiiL- U;LL;L t\Li][i.T :LIIL| ;itkjL;L[oJ lh^ LtL']>kjsi1nni ittimtjk.T C(']X'
I MO.W.
Can. l.ctl, Vo.3, Nr.. fl. 2001
1123
Overview of the Journal Article
55
proceeded smoothly in concent rued H.-SO; in high yield and
iiithoul racciiii/alion.
Removal of the phcnylacclamidc group under 2 Mm of
H: wilh catalytic Pd/C afforded (.VM^v-leucinc amide (t in
'J(>% i icld. Fiiiath.. ludroKsis of (he amide was accomplished b> heating in (i N" HC1 al UK] C 10 give (.S1)h'M-lcucine 7 in 8f>% yield and >l)S% cc. The absolute
configuration assignment, (X), was made by cotnparison wilh
an authentic sample."' Obviously, oilier noulcs to convert I he
ami no nilrtlc dcrivalucs to the ammo acid am be envisaged
and arc under invcsligalion.
The cryslalli/alion-indiiccd asymmetric transformation,
using t/^)-phcny[glycine amide I as cEiii'al atixilian itt
di;islereoselec[i\'c Strecker rcracliOEis. u';is further explored
11 ith 3.4-diinetho.\yphcinlaccloi)c 8 (Scheme 2).
Ttic optimi/cd ;isymmclric Slrcckcr rc;iclion of (!<)pheEiylglydne amide 1 (used as HC1 sail) and an cquimolar
amonnt of 3,4-dLmc|]io\j plicnylacetone S in McOH/H^O If)/1
v/v) gave, after adJilion of NaCN (30% atgiicnns salnlion)
and slirring for % h al room tcnipcritlLirc. llic nearly
diastereomcriailh pun: (dr > 'J'J/H amino niuilc 9 as a solid
in 76% isolated vicld. Ttic dr could casilv be determined bv
:
H NVIR analysis. It was found llial itt solution at room
tcnipci'alurc an equilibrium of 55:4? exists bclivccn Ihc Wo
diaSiKmomcre W..V)-!) and (/(JO-fl. Clearly, aiiain it eiv'SlalIJ/jilion-indiiccd as>inmetric iriinsrorniation has occurred.
In summary. (/0-phcnylglycine amide I is atl excellent
ctiiral an\iliar\- in the asymmetric Strcckcr reaction with
piviilddiydc or ^.4-diinel!ia\iphetiylaceU)nc. Nearly diastereomerically pure nmiiio nilriles can be obtained via a
crystalli/ation-induccd asymmetric iransformalion in ualcr
orwalcr/mcthanol. This ^radical onc-pol asymmclric Stiecker s>']illiesis of {y^..SV3 in M'ater leads to I lie slmtghlfonvard
synthesisof (.s'j-ftTf-lcucinc 7. Since (\/-phenyighcinc;iniide
is also a\ailablc. this can be used if Ihc oilier cnantiomeror
a target molecule is required. More examples arc currently
under invest igalion to extend the scope of I his procedure.vl
Acknowledgment. Mr A. Mcclsnia of the dcpannicnl
of ciysfallographj of llic Universily of Groningen is acknoii ledgcd for Ihe X-r;ii' strttcttirc of (H,S)-3.
Sit|)|)oittn<; Infuriimtiun Aviiilablc: Procedures and
diaraelcrralion dala of all compounds. This material is
available free of cliargevia Ihe Internet alhllp:/.'pubs.tics.org.
l)].l)mi)42L'
( |y>S^VC|-:ll H^ll^T^nl-! nitrilc^ i^oiiia h^ iilikiin^il -is ui^^ji!lirK jii;i1..TuU
Ironi ILI1 Mrfllt mixti .. i- s- Id ^ Tr. l(j - Hi Id -"I'll. It: - \L-. Id
= 't'r. H;= Mu. Comlil s :m hL'iii" sinjij]! Lii obUiiii Lils^ ;] Lr>sUilti/.LHLij]iindicial asMiiiHL'Irii lr;
1124
Crj. its.. Vol. 3, No. 6. 2001
56
The Journal Article
3
Writing the Methods Section
Tell me how you did it, but be concise. A long-winded step-by-step
Methods section sidetracks and irritates the expert reader.
—Betty H. Stewart, Midwestern State University
In this chapter, we focus on writing a Methods section for a journal-quality paper.
We begin with the Methods section because this is the section that many chemists write first, in part because this section describes what they know best: the
procedures they have repeated (many times) to conduct their work. Moreover,
most research groups use similar methodologies for several years; hence, previously written Methods sections can serve as models for writing new Methods sections. Together, these factors make the Methods section one of the easier sections
to write and an excellent place to begin our writing instruction. By the end of this
chapter, you will be able to do the following:
■
Know how to address the intended audience of a Methods section
■
Recognize which details to include and exclude from a Methods section
■
Organize a Methods section following standard moves
■
Use capitalization, abbreviations, and parentheses appropriately
■
Format numbers and units correctly
■
Use verb tense and voice in conventional manners
As you work through the chapter, you will write a Methods section for your own
paper. The Writing on Your Own tasks throughout the chapter will guide you
step by step as you do the following:
3A Read the literature
3B Describe materials
3C Describe experimental methods
3D Describe numerical methods
3E Practice peer review
3F Fine-tune your Methods section
The purpose of the Methods section is to address how a particular work was
conducted. Relevant information about instrumentation and experimental and/
or numerical procedures is described. The goal is to describe the information in
enough detail that an expert (not a novice) could repeat the work. Usually, this
section is formally called, for example, Materials and Methods or Experimental
Section, but for brevity, we call it simply the Methods section.
Methods Section
What we call the Methods section is given a more formal name in journal articles, such as
■
Materials and Methods
■
Experimental Section
■
Experimental Methods
Many of you have written a Methods section previously for a college-level chemistry course. Thus, we begin with an exercise to test your current knowledge about
writing a Methods section.
Exercise 3.1
What have you learned about writing Methods sections from other writing courses
and labs? Let’s evaluate your knowledge with the following pretest. In column 1,
place a “Yes” next to those items that you think should be included in a Methods
section of a journal article. Place a “No” next to items that you think should be
omitted. Use a question mark (?) if you are unsure. (You will use column 2 to
repeat this exercise at the end of the chapter.)
58
1
2
Possible Items for a Methods Section
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
A table of chemicals with their physical properties (e.g., mp, MW, ρ)
Amounts of reagents used in a synthesis (e.g., mg, mmol)
Directions for preparing a stock solution
The quality (grade) of chemicals used
The names and locations of chemical vendors
The brand names of commercial instrumentation used
A diagram of a distillation apparatus
An illustration of a novel or custom-built apparatus
Operating conditions for a gas chromatograph
The Journal Article
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
___
Equations used to calculate percent yield or dilution ratios
A list of disposable equipment (e.g., rubber gloves, Bunsen burners)
Step-by-step instructions of the procedure
Warnings to other scientists about unusual hazards
Quantitative statements of reaction times and temperatures
Descriptions of the physical appearances of synthesis products
IR or NMR data confirming product purity
Statistical packages used (including the name of the software)
Reports of other software used to keep track of data (e.g., Excel)
Reading and Analyzing Writing
We formally begin this chapter by asking you to read and analyze a Methods
section taken from an article in the Journal of Agricultural and Food Chemistry
pertaining to the chemical analysis of beer. (You will eventually read the entire
article, section by section, throughout the module.) The study involves international collaboration (researchers from the Miller Brewing Company in the United
States and the Institute of Chemical Technology in Prague, Czech Republic) and
employs one familiar analytical technique, gas chromatography/mass spectrometry (GC/MS), and another worth learning more about, solid-phase microextraction (SPME). The study focuses on aldehydes in beer because of their potential
role in affecting beer flavor and aroma. The authors developed a novel technique
involving SPME to measure low-level concentrations of aldehyde in beer during
storage.
Exercise 3.2
Read excerpt 3A below (a Methods section formally labeled Materials and
Methods). Consider the audience, organization, writing conventions, and grammar and mechanics used in the excerpt as you answer the following questions:
a. Who is the authors’ intended audience? How is this audience reflected in
level of detail, level of formality, and word choice?
b. How do the authors make their writing concise?
c. How do the authors organize their information?
d. What writing conventions do you notice (i.e., formatting, abbreviations, verb
tense, voice)?
e. Which passages correctly illustrate examples of parallelism (e.g., among
section headings), the use of commas, and subject–verb agreement?
Writing the Methods Section
59
f. What instrumentation did the authors use, and how is it described?
g. Based on your response to exercise 3.1, what information did you expect to
be in this Methods section that isn’t included?
Excerpt 3A (adapted from Vesely et al., 2003)
Materials and Methods
Chemicals. The carbonyl compound standards 2-methylpropanal, 2-methylbutanal,
3-methylbutanal, pentanal, hexanal, furfural, methional, phenylacetaldehyde, and
(E)-2-nonenal were purchased from Sigma-Aldrich (Milwaukee, WI). A stock solution containing a mixture of the standard compounds in ethanol was prepared daily
in a concentration of 100 ppb each. An aqueous solution of the derivatization agent
O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) (Sigma-Aldrich, Milwaukee,
WI) was prepared at a concentration of 6 g/L. PFBOA solution was prepared every 3
months and kept refrigerated.
Beer Samples. American lager beer samples used for the aldehyde analysis were
stored at 30 °C for 4, 8, or 12 weeks. Control samples were stored for 12 weeks at 0 °C.
The SO2 level of the fresh beer was 3.4 ppm, a low level for beer. Knowledge of the
SO2 level in beer is important because SO2 complexes with aldehydes and only “free”
aldehydes are measured by the described method.
SPME Fiber. A 65 μm poly(dimethylsiloxane)/divinyl benzene (PDMS/DVB) fiber
coating (Supelco, Bellefonte, PA) was used in this method. This fiber coating was
selected for its ability to retain the derivatizing agent and for its affi nity for the PFBOAaldehyde oxime (7).
Derivatization Procedure. One hundred microliters of PFBOA solution and
10 mL of deionized water were placed in a 20 mL glass vial and sealed with a magnetic crimp cap (Gerstel, Baltimore, MD). Initially, the PDMS/DVB SPME fiber was
placed in the headspace of the PFBOA solution for 10 min at 50 °C. The SPME fiber
loaded with PFBOA was exposed to the headspace of 10 mL of beer placed in a 20 mL
glass vial. Different derivatization times and temperatures as well as salt addition
were tested in order to obtain the best results. To ensure the reproducibility of the
method, an automated process using an MPS2 autosampler (Gerstel, Baltimore, MD)
was employed.
GC Conditions. Aldehyde derivatives were analyzed using a HP6890 gas chromatograph equipped with a mass-selective detector (5972A, Agilent Technologies, Palo
Alto, CA) and fitted with a DB-5 capillary column, 30 m × 0.25 mm × 0.50 μm (J&W
Scientific, Folsom, CA). Helium was the carrier gas at a flow rate of 1.1 mL/min.
The front inlet temperature was 250 °C. The injection was in the splitless mode with
the purge valve set at 30 s. The oven temperature program used was 40 °C for 2 min,
followed by an increase of 10 °C/min to 140 °C and 7 °C/min to 250 °C. The final
temperature was held for 3 min.
60
The Journal Article
Analyzing Audience and Purpose
The major purpose of a Methods section is to describe, for other chemists (the
audience), the procedures that were used to obtain the results presented in the
article. A well-written Methods section serves as a resource for expert chemists
who wish to (1) develop similar procedures, (2) compare their own procedures
with those presented, or (3) familiarize themselves with procedures in a branch
of chemistry other than their own.
Because Methods sections of journal articles are written largely for experts,
they are not at all like Methods sections of chemistry lab reports. Lab reports
are written largely for instructional purposes, to reinforce new techniques
and help students carry out experiments successfully. As such, they tend to
include details (e.g., lists of equipment, safety precautions, and step-by-step
directions) not needed (or wanted) by expert readers. Leaving out such details
makes the writing more concise. Concise writing is important because, unlike
a single lab experiment, methods sections in journal articles describe multifaceted works that took months or years to complete. Similarly, lab reports
often include language inappropriate for journal articles. For example, in the
Methods section of a lab report, a student might write “Stir mixture. Heat to
reflux.” In a journal article, however, this would be restated in past tense and
passive voice as “The mixture was stirred and heated to reflux,” making the
writing more formal.
Experiment vs. Work
Because of the multifaceted nature of a research project, authors seldom use the word
experiment, which connotes a simplistic activity that could be accomplished in a single day.
Words such as project or work are preferred.
To see for yourself how chemists write Methods sections for journal articles,
we have included excerpts from the published literature throughout this chapter.
These excerpts illustrate appropriate levels of detail, formality, and conciseness
when writing for expert chemists. We encourage you to use these excerpts (rather
than lab reports or lab manuals) as models for your writing.
Exercise 3.3
Compare the following excerpts that describe the process of recrystallization for
product purification. The first excerpt is adapted from an undergraduate laboratory experiment involving the extraction of caffeine from tea leaves. The last two,
written for expert audiences, are taken from articles in The Journal of Organic
Writing the Methods Section
61
Chemistry. What details are included for the expert audience? What details are
excluded?
a. The residue obtained in evaporation of the methylene chloride is next
recrystallized by the mixed-solvent method. Using a steam bath or hotplate,
dissolve the residue in a small quantity (about 2 mL) of hot acetone and add
dropwise just enough low-boiling (bp 30–60 °C) petroleum ether to turn the
solution faintly cloudy. Cool the solution and collect the crystalline product
by vacuum filtration, using a small Buchner funnel. (From Pavia et al., 1998)
b. Further purification was obtained by recrystallization from ethyl acetate/
hexane. (Adapted from Katritzky and Button, 2001)
c. Bis(p-tolyl) Trisulfide (2b). Yield 97%; recrystallization from n-pentane
at –15 °C afforded light yellow needles; mp 78–79 °C (lit. mp24 82–84 °C).
(From Zysman-Colman and Harpp, 2003)
Analyzing Organization
Most Methods sections follow a conventional organizational pattern. The pattern
typically involves two or three separate steps, each of which corresponds to a
move, as shown in figure 3.1. In accord with a common title for this section—
Materials and Methods—the moves describe first the materials and then the
methods (experimental and/or numerical) that were used in the work. Because
these moves describe specific information, the Methods section is in the narrowest part of the IMRD hourglass structure.
1. Describe Materials
(e.g., materials, chemicals, samples, cultures, sampling sites,
general reaction conditions)
2. Describe Experimental Methods
Describe procedure(s)
Describe instrumentation
3. Describe Numerical Methods (if applicable)
(e.g., statistical analyses, theoretical computations)
Figure 3.1 A visual representation of the move structure for a typical
Methods section.
62
The Journal Article
Move 1 tells readers about the materials used in the work. The term materials
refers to chemicals (e.g., solvents and reagents), samples (e.g., soil, water, or food),
biological media (e.g., bacterial cell cultures), and/or other tangible items used to
conduct the work (e.g., the SPME fiber used in excerpt 3A). In field studies, the
sampling site is also described in this move. When different types of materials
are used in one work, subheadings (shown here in bolded font) are commonly
used to set them off from one another (e.g., the subheadings Chemicals, Beer
Samples, and SPME Fibers were used in excerpt 3A). Subheadings commonly
used in move 1 include the following: Reagents and Materials, Samples, Cell
Cultures, and Site Description.
Move 1 is approached slightly differently in synthesis papers (e.g., articles published in The Journal of Organic Chemistry). Such papers typically describe a series
of related reactions, often totaling 10 or more individual syntheses. Rather than
describe all of the chemicals used for these many reactions at the start of the
Methods section, authors instead include only general information in move 1
(e.g., “All NMR studies were performed on a 500 mHZ instrument.”). A common
subheading for this move is General. Information about specific reagents and
materials are included in move 2, where the individual syntheses are described.
In move 2, Describe Experimental Methods (figure 3.1), authors describe how
they obtained their data. The move involves two submoves. The first submove,
describe procedures, includes analytical procedures (e.g., the steps used to prepare, extract, concentrate, and/or derivatize a sample), field-collection procedures (e.g., the steps used to collect water samples from a polluted lake), and
synthetic procedures (e.g., the steps used to synthesize target compounds), to
name only a few. In some journals (particularly those describing analytical procedures), this submove also includes procedures used to ensure the accuracy and
precision of the work. Such procedures are described as quality assurance/quality
control (QA/QC).
QA/QC
This abbreviation refers to quality assurance/quality control. QA/QC procedures are
standardized methods used to verify the quality (accuracy and precision) of data.
The second submove, describe instrumentation, describes the scientific apparatus used in the study. Both custom-built instruments (e.g., a high-vacuum chamber or a newly designed light source) and commercially available instruments
(e.g., a gas chromatograph or an infrared spectrometer) are described. Ordinary
lab equipment (e.g., a heating mantel or a rotary evaporator) is not described.
The submoves in move 2 are placed side by side in the move structure in
figure 3.1 to indicate that authors may present the submoves in either order, to
parallel the sequence of events in their study. For example, in excerpt 3A, the
Writing the Methods Section
63
derivatization procedure is described before the GC instrumentation because the
derivatization step was completed before the GC analysis. Alternatively, authors
who employ instrumental analysis early on in the study may describe instrumentation first.
Subheadings are also common in move 2. As in move 1, subheadings help
organize a paper that uses multiple methods. They also assist readers in quickly
locating a method of interest. (Scientists often read papers selectively, looking
only for information about a particular procedure or instrument.) The subheadings are often quite specific and include a name or description of the procedure
(e.g., HSSPME Extraction Procedure, or Fabrication of DNA Microarrays). In
synthesis papers, subheadings often name the compound synthesized (e.g., 2-(pToluenesulfonyl)-4′-methoxyacetophenone). Similarly, for instrumentation, the
subheadings specify the type of instrument (e.g., FTIR-Raman Measurements,
MALDI-TOF Mass Spectrometry, or Chromatographic Conditions).
The last move of the Methods section, Describe Numerical Methods, is
included only if numerical or mathematical procedures (e.g., statistical analyses) were used to analyze, derive, or model data presented in the paper. In such
cases, the experimental methods are described first (move 2), and the numerical
methods are described last (move 3). Subheadings used to demark move 3 include
Statistical Methods or Data Analysis.
Exercise 3.4
Consider the following sets of subheadings as you perform the following tasks:
a. We have intentionally scrambled the order of these subheadings. Using the
move structure in figure 3.1, arrange the subheadings in their correct order.
(In some cases, more than one ordering is correct.)
b. Look carefully at the subheadings for formatting (e.g., bolding, italics), abbreviations and acronyms, capitalization, and punctuation. What do you notice?
Set 1 Statistical Analysis.
FTIR Measurements.
Starch Samples.
FT-Raman Measurements.
Set 2 Time-of-Flight Mass Spectrometry (TOF).
Chemicals.
SPE and Cleanup.
Sample Pretreatment.
Set 3 Mutant Design.
Structure Determination.
Enzyme Kinetics.
Statistics.
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Exercise 3.5
Reconsider excerpt 3A in exercise 3.2. How well does the excerpt adhere to the
move structure represented in figure 3.1? How do the authors use subheadings to
help the reader locate the moves? Can you equate each subheading with one of
the moves? Are any moves left out? If so, which one(s)?
Exercise 3.6
Examine how the move structure in figure 3.1 applies across different fields of
chemistry.
a. Find two articles in The Journal of Organic Chemistry and two articles in
Organic Letters. How are the methods presented in these articles? What
subheadings are used? Do they adhere to the move structure suggested in
figure 3.1? Explain.
b. Find two articles with the word “theoretical” or “computational” in their
titles. How are the methods presented in these articles? What subheadings
are used? Do they adhere to the move structure suggested in figure 3.1?
Explain.
Upon completion of exercises 3.5 and 3.6, you probably noticed that not all written works in journals strictly adhere to the move structure in figure 3.1. Not surprisingly, the move structure does not apply to genres intended for a more general
audience (e.g., news alerts, book reviews, editorial remarks), nor does it apply to
all research-related works. For example, research articles published in Organic
Letters omit a Methods section entirely; instead, the procedures are published on
the Internet as supporting information.
Because of these variations, we end this section with a cautionary note:
Although the move structure in figure 3.1 presents a common and effective way
to organize your Methods section, it will not apply in all situations. Move structures vary from journal to journal and article to article; hence, ultimately you
must model your organizational structure after an article similar to the one that
you plan to write.
3A Writing on Your Own: Read the Literature
Read and review the Methods sections of the journal articles that you collected
during your literature search (see chapter 2). As you read these articles, pay attention
to how the authors organized their methods and what information they included.
How much detail is included in descriptions of materials, instrumentation, procedures,
Writing the Methods Section
65
and numerical methods? Are subheadings used? Do they help you navigate the
section?
What ideas do these articles give you about ways to write your own Methods section?
Analyzing Excerpts
With general audience and organizational considerations in mind, let’s next examine excerpts of Methods sections from the chemistry literature in more depth. We
analyze excerpts in two parts:
■
In part 1, we analyze excerpts move by move, focusing on levels of detail,
formality, and conciseness (including the noticeable absence of ordinal language), writing conventions (including capitalization, abbreviations, numbers, and units), and grammar and mechanics.
■
In part 2, we analyze excerpts for the purpose of examining the Methods
section as a whole, focusing on verb tense and voice.
Part 1: Analyzing Writing Move by Move
There is no question that, in every part of my career, clear and simple
writing has helped me communicate what I wanted said. In research, I
often have had comments about the clarity of my writing. I cannot but
think that this makes a favorable impression on reviewers. Although
clarity cannot supplant content, it certainly “encourages” reviewers, and
then readers, to spend some time with our work. Surely, that is what we
want when we bring something to press.
—Robert Damrauer, University of Colorado–Denver
Move 1: Describe Materials
The first move of the Methods section provides a description of chemicals, materials, and/or samples. Beginning writers often wonder what to include in this section (level of detail) and how these details should be presented (level of formality),
both issues related to audience. With respect to detail, it is customary to report
the name, purity, and vendor for all essential chemicals and materials used in
the work. (Incidental chemicals, e.g., solvents used to clean glassware, need not
be reported.) Similarly, for samples, both how and where the samples were collected should be described. With respect to formality, the journal article requires
complete sentences. A common mistake is to use lists; although commonplace in
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lab reports, lists should be avoided in journal articles because they often are
fragments rather than complete sentences. Consider the following incorrect and
correct examples:
Incorrect Chemicals. Solvents (Aldrich): 99.8% purity methanol,
97% purity ethanol, 99% purity 1-pentanol, 99% purity
1-hexanol.
Correct Chemicals. Methanol (99.8% purity), methyl formate (97%
purity), 1-pentanol (99% purity), and 1-hexanol (99% purity) were
purchased from Aldrich.
Correct Chemicals. The following solvents were purchased from Aldrich:
methanol (99.8% purity), methyl formate (97% purity), 1-pentanol
(99% purity), and 1-hexanol (99% purity).
In the correct examples, complete sentences were used (achieved by adding the
words “were purchased from Aldrich”). Also, parentheses were used for solvent
purity, making the solvent names easier to read.
Fragments
Fragments are incomplete sentences. When writing your journal-quality paper, be sure to
use complete sentences. Do not use lists or fragments.
Exceptions include (1) titles, (2) section headings, (3) figure captions, and (4) table titles.
When more than one vendor is involved, chemicals are typically grouped by
vendor. It is customary to include the location of vendors (city, country) the first
time a vendor is mentioned. Typically, the location is reported in parentheses at
the end of the sentence, as shown in excerpts 3B and 3C.
Excerpt 3B (from Llompart et al., 2001)
Experimental Section
Reagents and Materials. The PCB congeners, 2,4,4′-trichlorobiphenyl (PCB-28),
2,2′,5,5′-tetrachlorobiphenyl (PCB-52), 2,2′,4,5,5′-pentachlorobiphenyl (PCB-101),
2,3,3′,4,4′-pentachlorobiphenyl (PCB-105), 2,3′,4,4′,5-pentachlorobiphenyl (PCB-118),
2,2′,3,4,4′,5′-hexachlorobiphenyl (PCB-138), 2,2′,3,4,4′,5′-hexachlorobiphenyl (PCB-153),
2,3,3′,4,4′,5′-hexachlorobiphenyl (PCB-156), and 2,2′,3,4,4′,5,5′-heptachlorobiphenyl
(PCB-180) (PCB numbering according to IUPAC) were supplied by Ultra Scientific
(North Kingstown, RI). Isooctane, acetone, and sodium hydroxide were obtained
from Merck (Mollet del Valles, Barcelona, Spain). All the solvents and reagents were
analytical grade.
Writing the Methods Section
67
Excerpt 3C (adapted from Plaper et al., 2002)
Experimental Procedures
Media, Chemicals, and Bacterial Strains. Proteinase K, ethylenediamine-tetraacetic acid (EDTA), tris(hydroxymethyl)aminomethane (Tris), o-nitrophenyl-β-Dgalactopyranoside (ONPG) powder, tRNA, agarose, 3-4,5 dimethylthiazol-2,5 diphenyl
tetrazolium bromide (MTT), ICR-191, and ethidium bromide were from Sigma (St. Louis,
MO). Polymyxin B sulfate, Triton X-100, and 1,4-dithio-DL-threitol (DTT) were from
Fluka Chemie (Buchs, Switzerland). Bacto yeast and Bacto trypton, used in LB medium,
were from Difco (Detroit, MI). Chromium chloride (CrCl 3•6H 2O) and chromium
nitrate (Cr(NO3)3•9H 2O) were from Merck (Darmstadt, Germany). Chromium oxalate
(KCr(C2O4)2•3H 2O) was from Aldrich (Milwaukee, WI). Gyrase was from TopoGEN
(Columbus, OH), and pUC19 plasmid DNA was from Promega (Madison, WI). All Cr3+
solutions were made fresh daily and diluted as required in sterile doubly distilled water
immediately prior to use.
Excerpt 3D illustrates two additional points regarding naming chemicals in
move 1: First, if all chemicals used were of the same grade and from the same
company, state only the grade and company, not the names. The names will be
mentioned in move 2, when the procedures in which the chemicals were used
are described. Second, only those chemicals that were used as received, required
minimal preparation (e.g., distilling or degassing), or were prepared according to
literature methods (which should be cited in the text) are mentioned. Chemicals
that require more detailed preparation steps are described in move 2.
Excerpt 3D (adapted from Ahmed et al., 2002)
Experimental Section
Reagents and Materials. All the chemicals used were of high grade purity and were
obtained from E. Merck (Darmstadt, Germany). The standard reference material for Li
was L-SVEC in Li2CO3 form. The ion exchangers, both anion and cation types, were
prepared in our laboratory as described elsewhere.8 Pure and Na-free SiO2 gels were
prepared in our laboratory by refinement of the procedure reported in the literature.9,10
Chemicals that are used as reference standards are also commonly described
in move 1. As with other chemicals, the name, purity, and vendor should be
included. Moreover, the final concentration of any stock standard solution should
be mentioned (in addition to any other dilute solutions prepared from the stock
solution). Do not explain how a stock solution (or any solution) was prepared;
simply state the final concentration and solvent (e.g., 100 µg/L in ethanol), as
illustrated below and in excerpt 3E.
Incorrect The internal standard phenanthrene-d10 was prepared by
adding 1 mL of a 2000 µg/mL solution to a 50 mL volumetric
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Correct
flask and diluting to the mark with hexane (final concentration
40 ng/µL).
Phenanthrene-d10 was used as the internal standard (40 ng/µL in
hexane).
Excerpt 3E (adapted from Aguilera et al., 2003)
Reagents. (a) Pesticide standards of acephate, bromopropylate, chlorpyrifos,
chlorpyrifos-methyl, chlorothalonil, diazinon, dichlorvos, endosulfan I, endosulfan II,
endosulfan sulfate, lindane, methamidophos, phosalone, procymidone, pyrazophos,
triazophos, and vinclozoline (purity >98%) were supplied by Riedel de Haen (Seelze,
Germany). For each pesticide, a stock standard solution (about 500 mg/L) was prepared
in acetone. Spiking standard solution, containing 50 mg/L of each pesticide, was prepared in acetone from the stock standard solutions.
Exercise 3.7
Imagine that you prepared a stock standard solution of arsenic in your research
project. You purchased an arsenic concentrated standard (1000 µg/mL) from Spex
Industries in Hoboken, New Jersey. You prepared a 100 µg/mL stock standard
solution by adding 10 mL of the concentrated standard to a 100 mL volumetric
flask and diluting to the mark with deionized water. How would you report this
information in the Methods section of a journal article?
Deionized ≠ DI
Many beginning writers ask if they can use DI for deionized water or DD for doubledistilled water. Using the ACS Journals Search, we found that both phrases appear more
commonly in written-out form than in abbreviated form.
Samples are treated much like chemicals (excerpts 3F–3H). Complete sentences are used, and information is shared about the sample source and selection
process. If sample collection follows an established procedure (e.g., a U.S. EPA
protocol), that should be noted in the text (see excerpt 3H).
Excerpt 3F (adapted from Ozen and Mauer, 2002)
Materials and Methods
Samples. Eleven hazelnut oils, 25 olive oils, and 7 other types of oil (canola, soybean, corn, sunflower, sesame, walnut, and peanut) were purchased from local grocery
stores and Internet suppliers. For the adulteration studies, 10 olive oil and 10 hazelnut
oil brands were randomly chosen from the samples purchased, and blends of olive oil
Writing the Methods Section
69
and hazelnut oil were prepared by mixing these oils. The hazelnut oil blend was adulterated with sunflower oil at 2–10% (v/v), and the blend of extra-virgin olive oils was adulterated with the hazelnut oil blend at 5–50% (v/v). Infrared spectra of pure oil samples
(25 virgin olive oils, 11 hazelnut oils, and canola, soybean, corn, sunflower, sesame,
walnut, and peanut oils) and adulterated samples then were obtained.
Excerpt 3G (adapted from Kunert et al., 1999)
Materials and Methods
Sampling. The moss samples were taken from a 30- to 40-year-old spruce forest
(Hoerner Bruch) southeast of Osnabruck (F.R.G.). Starting in September 1985, samples
were taken regularly (usually at weekly intervals) from 50–100 individual plants of
P. formosum on an area of approximately 1 m2 and made up into a mixed sample. The
individual samples were picked about 1 cm above the soil. These samples represent a
period of time of 2–3 years, and the content of metals reflected a measure of the atmosphere deposition during that period (32). Gloves were worn during sampling, and only
synthetic materials were used. Attention was given to pick the moss samples without
soil contamination. Markert and Weckert (33–35) have given detailed descriptions of the
moss P. formosum in this area, which means that a large amount of background information was available. These investigations showed that it was sufficient to measure lead
isotope ratios in four regularly selected samples per year (spring, summer, autumn, and
winter).
Genus and Species Names
Genus names, as formal names, should be capitalized and italicized. Species should not
be capitalized, but they should be italicized. Genus names are spelled out in full at first
mention and abbreviated thereafter.
Seasons
Seasons of the year (fall, spring, summer, winter) should not be capitalized.
Excerpt 3H (adapted from Dellinger et al., 2001)
Experimental Section
Sample Collection. Multiple samples of PM2.5 that were used in the mechanistic
studies were collected at the Louisiana Department of Environmental Quality station
0.1 mi from Interstate highway I-10 and 1.5 mi east of the junction of I-10 and I-12
in Baton Rouge, LA, using the U.S. EPA protocol RFPS-0498–117 and a Rupprecht &
Patashnick Partisol-FRM model 2000 air sampler. Samples of PM2.5 from the other four
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sites were furnished by the EPA. They were collected using URG MASS 400 samplers as
part of a sampler evaluation program conducted at EPA’s “supersites” for ambient air pollution research (32). All samples were collected over a 24 h period except for 2 and 5 day
samples from the Baton Rouge site, which were utilized in the mechanistic studies.
Unabbreviated Units of Time
The following units of time are not abbreviated: day, week, month, and year.
Exercise 3.8
Look over excerpts 3B–3H. Propose rules that describe the appropriate use of
capitalization, abbreviations, parentheses, sentence fragments, numbers (spelled
out or in number form), and units.
As mentioned above, organic synthesis papers seldom describe the chemicals in
the first move; instead, the move is used to summarize general reaction conditions. Two examples are given in excerpts 3I and 3J:
Excerpt 3I (from Swenson et al., 2002)
Experimental Section
General. All reactions were performed under nitrogen. 1H NMR and 13C NMR spectra were recorded in ppm (δ) on a 300 MHz instrument using TMS as internal standard.
Elemental analyses were performed by Robertson Micolit Laboratories. Anhydrous THF,
toluene, and tert-butyllithium in pentane (1.7 M) were purchased. Flash chromatography
was performed with silica gel 60 (230–400 mesh). Melting points were determined and
are uncorrected.
Excerpt 3J (adapted from Demko and Sharpless, 2001)
Experimental Section
General. All 1H NMR spectra were taken on a Bruker AMX-400 spectrometer in
DMSO-d6 with DMSO as a standard at 2.50 ppm. All 13C NMR spectra were taken on the
same machine at 100 MHz in DMSO-d6 with DMSO as a standard at 39.50 ppm, unless
otherwise noted. All melting points were taken on a Thomas-Hoover Uni-melt melting
point apparatus. Reagents were used unpurified, and deionized water was used as the
solvent.
Move 1 of the Methods section, because it describes compounds and materials,
is an excellent place to examine writing conventions regarding capitalization.
As you read excerpts 3B–3J, you probably noticed that chemists are a bit picky
Writing the Methods Section
71
about what is capitalized and what is not. Most novice writers know (correctly) to
capitalize the following:
Molecular formulas
Vendors and brand names
Select abbreviations
Absolute configuration (R and S)
F–, CrCl3, H2O
Alltech, Ultra Scientific
THF, PCB, NMR, EPA, ACS
(R)-glyceraldehyde
Capitalization
See appendix A.
Italics
Words (and their abbreviations) that indicate spatial orientation are italicized, for example,
cis, trans, o, m, p, (R), and (S).
Except for (R) and (S), which are always uppercase, the others are always lowercase,
even at the start of a sentence, for example,
o-Benzene. . .
trans-Butene. . .
(S)-Lactic acid. . .
However, novice writers also tend to capitalize words that should be written
entirely in lowercase letters. For example, the names of molecules, compounds,
and solvents are all written in lowercase:
The reaction of 6-octadecynoic acid (tariric acid) with potassium permanganate yields dodecanoic and 1,6-hexanedioic acid.
Acid-catalyzed dehydration of 2,2-dimethylcyclohexene in ether yields a
mixture of 1,2-dimethylcyclohexene and isopropylidenecyclopentane.
The names of compounds are capitalized only at the start of a sentence, in which
case only the first letter is capitalized. Even at the start of a sentence, words that
signal stereochemistry—such as ortho (o), meta (m), para (p), cis, and trans—are
lowercase (and italicized).
1,3-Dibromo-5-chlorobenzene was added to Br2 and FeBr3.
cis-2-Bromo-3-methylcyclohexane was added to (R)-lactic acid.
p-Toluenesulfonic acid reacts with NaOH and acid workup to form p-cresol.
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Lowercase letters are also used for units derived from surnames when they appear
in spelled-out form and do not follow a number. The abbreviated form, used as a
unit after a number, is capitalized. Celsius and Fahrenheit are always capitalized
because they refer to temperature scales (not actual units).
The temperature was measured in kelvins and converted to degrees Celsius.
The temperature was 298 K (25 °C).
Units of Measure from Surnames
Surnames that are used as units of measure, when not preceded by numbers, should be
written in lowercase letters. For example,
ampere
angstrom
coulomb
curie
einstein
hertz
joule
kelvin
newton
ohm
pascal
watt
For more extensive guidelines, consult The ACS Style Guide.
Additional examples of appropriate and inappropriate uses of capitalization
are shown in table 3.1.
Exercise 3.9
Reexamine excerpts 3B–3J. Which words are written in lowercase letters that you
expected to be capitalized and vice versa?
In addition to capitalization, move 1 of the Methods section is also an excellent
place to examine how chemists use abbreviations and acronyms in their writing.
Abbreviations are short forms of words or phrases where each letter is often
pronounced (e.g., DNA); acronyms are short forms of words or phrases that form
pronounceable words (e.g., NASA). Both are common in chemical writing, in part
because they make the writing more concise. A few abbreviations are so common
that they can be used without ever introducing the full term (e.g., DNA, IR, NMR,
UV, RNA). Most abbreviations, however, need to be defined before they can be
used on their own; in such cases, abbreviations are placed in parentheses immediately following the full terms that they represent. For example,
Writing the Methods Section
73
Table 3.1 Capitalization rules followed in most journal articles.
Correct
Incorrect
As shown in Figure 2,
As shown in figure 2,
As shown in Scheme 1,
As shown in scheme 1,
As shown in Table 4,
As shown in table 4,
BF3, a Lewis acid, was used to . . .
BF3, a Lewis Acid, was used to . . .
The reaction was heated to 300 K.
The reaction was heated to 300 k.
The reaction was conducted under nitrogen.
The reaction was conducted under Nitrogen.
3-Bromobenzene and 3-chloropropane . . .
3-Bromobenzene and 3-Chloropropane . . .
The metals were lead, zinc, and tin.
The metals were Lead, Zinc, and Tin.
In the Southwest and in northern Arizona,
In the southwest and in Northern Arizona,
The disease is caused by Salmonella typhimurium.
The disease is caused by Salmonella Typhimurium.
UV–vis spectroscopy was used to . . .
UV–Vis spectroscopy was used to . . .
A differential scanning calorimeter (DSC) . . .
A Differential Scanning Calorimeter (DSC) . . .
■
2,4,4′-trichlorobiphenyl (PCB-28)
■
3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)
■
ethanol (EtOH), methanol (MeOH), and acetonitrile (ACN)
After an abbreviation or acronym has been defined, the abbreviated form may be
used alone without parentheses. The full form may also be used again, if it seems
more appropriate, but the abbreviated form should not be defined again. Note
also that most abbreviations and acronyms are used without periods (e.g., NMR
not N.M.R.).
Abbreviations
An abbreviation is a shortened form of a word. In some cases, the individual letters are
pronounced, as in ACS.
The ACS Style Guide lists some abbreviations that need not be defined for expert audiences, (e.g., DNA, IR, RNA, and NMR).
Other abbreviations need to be written out in full form before using the abbreviated
form, for example, tetrahydrofuran (THF). See The ACS Style Guide for a long list of accepted
abbreviations.
The ACS Style Guide includes a long list of accepted abbreviations to discourage
authors from creating their own. Moreover, authors should not use abbreviations
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that result from laboratory slang. For example, DI, DD, RT, and LN2 (slang for
deionized water, double-distilled water, room temperature, and liquid nitrogen,
respectively) should not be used in formal writing. A few incorrect and correct
examples are illustrated below.
Incorrect The rxn proceeded for 3 h.
Correct The reaction proceeded for 3 h.
Incorrect The % yield was affected by adding NaBr.
Correct The percent yield was affected by adding NaBr.
Incorrect The product was washed 3x in DD water.
Correct The product was washed three times in double-distilled water.
Correct The produce was washed in double-distilled water (3 × 10 mL).
Incorrect Surrogate standards (SS) and internal standards (IS) were used.
Correct Surrogate standards and internal standards were used.
Some approved chemical abbreviations and acronyms, with their spelled-out
equivalences, are given in table 3.2. When in doubt if an abbreviated form is
correct, check The ACS Style Guide or search the literature (using, e.g., the search
engine on the ACS Web site).
Abbreviations and Acronyms
See appendix A.
Another type of abbreviation—a bolded number, sometimes followed by a
letter—is used to label reagents, products, or other compounds that are mentioned more than once in the text. (This is a useful convention because compounds can often be more than 100 characters in length!) Bolded numbers are
also used to label species in reactions and schemes, so that the species can later
be referred to by number. In the text, the bolded number is introduced, sometimes in parentheses, immediately after the first usage of the full name, like other
types of abbreviations. Subsequent references to the compound are by bolded
number (and possibly a letter) only, without the full name and without parentheses. Numbers are assigned sequentially if more than one compound is labeled in
the text.
In the following example, compound 2a is the second labeled compound and
the first of several related compounds in the 2 series. The number is introduced
in the subheading and used again in the subsequent text.
2-(p-Toluenesulfonyl)-4′-methoxyacetophenone (2a). A mixture of 2 bromo-4′methoxyacetophenone (45.8 g, 200 mmol) and p-toluenesulfinic acid sodium hydrate
Writing the Methods Section
75
Table 3.2 Common abbreviations in chemistry (adapted from The ACS
Style Guide: Coghill and Garson, 2006).
Instrumental Techniques
atomic absorption spectroscopy
atomic force microscopy
electron-capture detector, detection
electron spin resonance
flame ionization detector, detection
Fourier transform infrared
high-performance liquid chromatography; high-pressure
liquid chromatography
inductively coupled plasma
mass spectrometry; mass spectrum
scanning electron microscopy
secondary-ion mass spectrometry
solid-phase microextraction
thin-layer chromatography
transmission electron microscopy
X-ray diffraction
X-ray fluorescence
AAS
AFM
ECD
ESR
FID
FTIR
HPLC
ICP
MS
SEM
SIMS
SPME
TLC
TEM
XRD
XRF
Units of Measure
atomic mass unit
centimeters
degrees Celsius
degrees Kelvin
disintegrations per second
foot/feet
gram(s)
hour(s)
inch(es)
liter(s)
liters per minute
meter
microgram(s)
milligram(s)
milliliter(s)
millimeter(s)
millimolar
minute(s)
molar (mol L –1)
nanogram(s)
parts per billion
76
amu
cm
°C
K
dps
ft
g
h
in.
L
lpm
m
μg
mg
mL
mm
mM
min
M
ng
ppb
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Table 3.2 (continued)
parts per million
second(s)
volume per volume
ppm
s
v/v
Chemical Structures
acetate
adenosine 5′-triphosphate
chlorofluorocarbon
dimethyl sulfoxide
ethyl
ethylenediaminetetraacectic acid
inosine 5′-triphosphate
messenger RNA
methyl
methanol
minimum Eagle’s essential medium
polychlorinated biphenyl
tris(hydroxymethyl)aminomethane
AcO
ATP
CFC
DMSO
Et
EDTA
ITP
mRNA
Me
MeOH
MEM
PCB
Tris
Statistical Symbols
correlation coefficient
degrees of freedom
probability
relative standard deviation
sample variance
standard deviation
standard error
standard error of the mean
total number of individuals
r
df
p, P
RSD
s2
σ, SD
SE
SEM
n, N
Miscellaneous
and others
anhydrous
boiling point
calculated
dose that is lethal to 50% of subjects
enantiomeric excess
inside diameter
lethal dose
mass-to-charge ratio
melting point
molecular weight
ultrahigh vacuum
Writing the Methods Section
et al.
anhyd
bp
calcd
LD50
ee
i.d.
LD
m/z
mp
Mr, MW
UHV
77
(35.6 g, 200 mmol) in ethanol (1 L) was heated at reflux for 1.5 h. The mixture was
stirred and cooled to room temperature, and the resulting solid was collected, washed
with ethanol (2 × 50 mL), dried to give 54.6 g (90%) of pure 2a: mp 126.0–127.0 °C;
IR 2951, 2906, 1676, 1599, 1572 cm–1; 1H NMR (CDCl3) δ 2.45 (s, 3H). (From Swenson
et al., 2002)
In reactions and schemes, the bolded number is centered below the species
and used without parentheses. For example, 1 and 2 represent bromomethane
and methanol, respectively:
CH3Br + HO – → CH3OH + Br –
1
2
Exercise 3.10
Look over excerpts 3B–3J again quickly. What types of information are presented
in parentheses? For unfamiliar abbreviations in the excerpts, refer to table 3.2 for
full terms.
Exercise 3.11
Consider the abbreviations used in the Methods sections of the journal articles
that you have selected for your writing project. Make a list of these abbreviations
and their definitions. (Note: Look for definitions earlier in the article if the abbreviations are used without definition in the Methods section.)
Exercise 3.12
Improve the following excerpt so that it uses capitalization, abbreviations, acronyms, parentheses, and complete sentences correctly:
Chemicals and Materials. Boric Acid and Methanol from Riedel-de Haën (Seelze,
Germany). All peptides from Sigma (St. Louis, MO). 4-Amino-1-Naphthalenesulfonic acid
(A.N.S.A.) from Aldrich (Steinheim, Germany). Sodium Nitrite and Cuprous Bromide,
98%, from Acros (Geel, Belgium) and HBr, 48%, from Fluka (Buchs, Switzerland). Used
chemicals as received. (Adapted from Kuijt et al., 2001)
Exercise 3.13
Rewrite the following list of chemicals in a way that is appropriate for the Methods
section of a journal article. Assume that all chemical compounds (i.e., reagents
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and solvents) were research grade and were purchased from Sigma-Aldrich in
Milwaukee, Wisconsin.
■
2-Bromopropane
■
Calcium chloride, anhydrous
■
Magnesium sulfate, anhydrous
■
Solvents: Distilled ethanol, acetonitrile, and dichloromethane
3B Writing on Your Own: Describe Materials
What chemicals, samples, and/or general conditions do you plan to describe in your
Methods section? Prepare a list of these items, including any necessary supplementary
information such as vendor, grade, and/or purity.
Convert your list into prose (using complete sentences), thereby writing the first move
(Describe Materials) of your Methods section. Be sure to include an appropriate subheading for this section (e.g., Chemicals, Materials, or Samples).
Move 2: Describe Experimental Methods
Move 2 is typically the longest move in the Methods section. As shown in figure 3.1, move 2 involves two submoves (describe procedures and describe instrumentation), which can be addressed in either order. Each submove is addressed
separately below.
Describe Procedures
Many of you have already described procedures in a lab report. Most likely, you
included items such as the equation that you used to calculate percent yield or
the step-by-step instructions that you followed to complete a synthesis (e.g.,
“Heat to reflux.” or “Stir constantly for 10 min.”). Are such items also appropriate in a journal article? To answer this question, we analyze several different
excerpts. Each excerpt describes a common chemical procedure. Although by
no means comprehensive, these few examples should get you started and help
you understand what an expert audience expects in this move of the Methods
section.
We begin with two excerpts that describe organic syntheses (excerpts 3K
and 3L). Both excerpts begin with a subheading. In the first excerpt, the subheading is the name of the specific compound that was synthesized. In the second
excerpt, the subheading refers to a general procedure for synthesizing a class
of compounds (tetrazoles). The excerpts then go on to describe the steps in the
synthesis.
Writing the Methods Section
79
Exercise 3.14
Read excerpts 3K and 3L and answer the following questions:
a. Different units are used to describe the amounts of reactants, solvents, and products.
What are those units? Include correct punctuation and capitalization.
b. For what procedures are time and temperature reported?
c. What information is included about washing the products?
d. How is the writing style in excerpts 3K and 3L different from the writing style of
most lab reports?
Excerpt 3K (adapted from Swenson et al., 2002)
2-(p-Toluenesulfonyl)-4′-methoxyacetophenone (2a). A mixture of 2-bromo-4′methoxyacetophenone (45.8 g, 200 mmol) and p-toluenesulfinic acid sodium hydrate
(35.6 g, 200 mmol) in ethanol (1 L) was heated at reflux for 1.5 h. The mixture was
stirred and cooled to room temperature, and the resulting solid was collected, washed
with ethanol (2 × 50 mL), and dried to give 54.6 g (90%) of pure 2a: mp 126.0–127.0 °C;
IR (cm–1): 2951, 2906, 1676, 1599, 1572; 1H NMR (400 MHz, CDCl3): δ 2.45 (s, 3H),
3.90 (s, 3H), 4.67 (s, 2H), 6.95 (d, J = 8.8 Hz, 2H), 7.34 (d, J = 8.2 Hz, 2H), 7.76 (d, J =
8.2 Hz, 2H), 7.95 (d, J = 8.8 Hz, 2H); 13C NMR (CDCl3): δ 20.9, 55.1, 62.5, 113.4 (2C),
127.7 (2C), 128.3, 129.1 (2C), 131.1 (2C), 135.8, 144.3, 163.7, 186.0. Anal. Calcd for
C16H16O4S: C, 63.14; H 5.30; S, 10.54. Found: C, 63.49; H, 5.35; S, 10.33.
Excerpt 3L (adapted from Demko and Sharpless, 2001)
Large-Scale, Organic Solvent-Free Procedure for the Synthesis of Tetrazoles. To
a three-necked 3 L round-bottomed fl ask equipped with a mechanical stirrer was added
benzonitrile (103.1 g, 1.00 mol), 1 L water, sodium azide (68.2 g, 1.05 mol), and zinc
chloride (68.1 g, 0.50 mol). The reaction was refluxed in a hood, but open to the atmosphere, for 24 h with vigorous stirring. After the mixture was cooled to room temperature, the pH was adjusted to 1.0 with concentrated HCl (~120 mL), and the reaction was
stirred for 30 min to break up the solid precipitate, presumably (PhCN4)2Zn. The new
precipitate was then filtered, washed with 1 N HCl (2 × 200 mL), and dried in a drying
oven at 90 °C overnight to give 98.0 g of 5-phenyltetrazole as a white powder (67%
yield, mp 211 °C (lit.25 216 °C)).
Reporting Analytical Data
In most synthesis papers, analytical data confirming product purity or composition are
reported in the Methods section, not the Results section.
Excerpt 3K illustrates a conventional way to format mp, IR, NMR, and quantitative analysis. See The ACS Style Guide for other examples.
80
The Journal Article
Units and Verb Agreement
Use a singular verb when one unit of measure is mentioned. Use a plural verb when two
separate units of measure are mentioned.
Incorrect To the mixture were added 8.5 g of X.
Correct To the mixture was added 8.5 g of X.
Correct To the mixture was added X (8.5 g).
Correct To the mixture were added 8.5 g of X and 6.5 g of Y.
What details did you notice in excerpts 3K and 3L? Did you notice that both
excerpts included the mass and moles of solid reagents, reaction times and temperatures, descriptions of the products (a solid, a white powder), and product
yields? Both excerpts also included results from tests used to verify product purity
and composition. The first included mp, IR, 1H NMR, and mass spectral information; the second included only mp information. Perhaps you were surprised to see
such “results” in the Methods sections. Synthetic chemists include such analytical information as part of the procedure, in the Methods section, rather than as
a result, in the Results section. The formatting shown in excerpt 3K is typical for
the presentation of such data.
There were also differences between the two excerpts. For example, no mention was made of a flask or beaker in excerpt 3K; however, the authors mention
a three-necked 3 L round-bottomed fl ask in excerpt 3L. Similarly, no hood is
mentioned in excerpt 3K, but the authors mention a hood, open to atmosphere, in
excerpt 3L. What principles guided these decisions? Although there are no hard
and fast rules, you should include common details (e.g., a flask or hood) only if
you want to draw attention to those steps (as in excerpt 3L). (See figure 3.2.)
We have summarized a list of the most common details included in a synthesis in table 3.3, along with a list of what not to include. From these lists, it
is clear that the journal article is not intended to teach a novice chemist how to
conduct a first experiment. Instead, the journal article serves as a blueprint for
Figure 3.2 “Every little detail” is too much detail for experts (and Snoopy). PEANUTS: ©United
Feature Syndicate, Inc.
Writing the Methods Section
81
Table 3.3 Details commonly included and omitted when describing a chemical synthesis.
Details Commonly Included
Details Commonly Omitted
• a specialized type of glassware
• the equation used to calculate yield
• the mass and moles of solid reagents or volume
of liquid reagents (often in parentheses)
• a list of disposables (gloves, pipettes)
• information on the reaction time and temperature
• information on stirring
• information on how the product was filtered,
washed, and dried (including solvents used and their
amounts)
• the final product mass and percent yield
• a description of the final product (a solid, a white
powder)
• names of common glassware (funnels,
beakers)
• steps taken in routine procedures
(weighing, diluting, purifying)
• mistakes made (e.g., spilling the
product) (Note: If such mistakes
are made, the synthesis must be
repeated!)
• analytical information about the product (mp, IR, 1H
NMR, and mass analysis)
the experienced chemist. In other words, the recipe is included, but basic cooking
instructions are not.
We next focus on how authors describe a synthesis. As noted previously, command language should be avoided; moreover, the procedures should not read
like a checklist of things to do. To get you started, we present “formulas” for
three commonly described synthetic procedures. The formulas illustrate common organizational structures and phrases (e.g., the organic layer, the aqueous
layer, the crude product) used to describe simple synthetic techniques such as
refluxing, quenching, and purifying. By using these formulas and phrases, your
writing will be more concise, and you will sound more like an expert. Note that
the italicized passages in these examples will vary with each synthesis:
Describing a Synthesis
Phrases commonly used to describe a synthesis include the following:
82
■
heated to reflux
■
heated at reflux
■
cooled to room temperature
■
the organic layer
■
the aqueous layer
■
the/an aqueous solution
The Journal Article
■
the reaction mixture
■
the resulting mixture
■
the crude product
Formula 1: To describe how to prepare a mixture and heat at reflux
■
A mixture of X (g, mmol), Y (g, mmol), and Z (g, mmol) in A (x mL) was heated
at reflux for 1.5 h and cooled to room temperature.
■
To a mixture of X (g, mmol) and Y (g, mmol) in A (x mL) was added Z
(g, mmol). The mixture was heated at reflux for 2 h and cooled to room
temperature.
Formula 2. To describe how to continue and stop a reaction
■
After x min, a solution of X (g, mmol) and Y (g, mmol) in A (x mL) was added
to the mixture. The mixture was stirred at 10 °C for 1 h, warmed to room temperature, and quenched with saturated aqueous ammonium chloride (5 mL).
Formula 3. To describe how to extract, wash, and purify a product
■
The water phase was extracted with X (2 × 10 mL). The combined organic
layers were washed with Y (2 × 10 mL) and Z (2 × 10 mL), dried with MgSO4,
and evaporated in vacuo. The crude product was recrystallized from ethanol
at –10 °C and further purified using column chromatography.
Exercise 3.15
Using excerpt 3K as a guide, rewrite the following 1H NMR data in the appropriate format:
The 1H NMR (400 MHz) solvent was CDCl 3. Two different sets of nonequivalent hydrogens were detected. The fi rst set resonated at a chemical shift of 2.4 ppm (a singlet with
an integrated area equal to 3H). The second set resonated at a chemical shift of 3.9 (also
a singlet with an integrated area equal to 3H).
Exercise 3.16
Find three synthesis articles in The Journal of Organic Chemistry. Compare the
Methods sections in these articles with excerpts 3K and 3L. Which of your three
articles, if any, include the same types of information that you reported in parts
a, b, and c of exercise 3.14?
Writing the Methods Section
83
Exercise 3.17
Rewrite the following synthetic procedure (adapted from D’hooghe et al., 2004)
using language appropriate for a journal article. The five steps listed (a–e) are
from a single procedure involving multiple steps. Note the use of bolded numbers
in steps d and e.
a. Make a solution containing 15 mmol (3.60 g) of 2-(bromomethyl)-1-((4methylphenyl)methyl)aziridine in 50 milliliters of acetonitrile.
b. Add 2.56 g (15 mmol) of benzyl bromide.
c. Heat the solution for 5 hours, refluxing.
d. Remove the solvent using a vacuum to produce N-benzyl-N-(2,3dibromopropyl)-N-((4-methylphenyl)methyl)amine (4).
e. Purify the crude product using column chromatography on silica gel, eluting
with a mixture of hexane and ethyl acetate. A typical yield of purified 4 is 85%.
We now consider procedures that do not involve synthesis (excerpts 3M–3O).
There are literally hundreds of such procedures in chemistry; however, these few
excerpts illustrate essential features of how such procedures are generally written.
As in syntheses, nonsynthetic procedures begin with a descriptive subheading;
following the subheading, the procedure is described in concise, complete sentences, including only those details needed by an expert audience. Such details
are often quantitative in nature (e.g., the number of cells to plate). Information
that is largely for students (e.g., “zero the balance”) or available elsewhere (e.g.,
instructions from an operator’s manual) is omitted.
Also like syntheses, a clear order of events is conveyed in the procedure. Novice
writers inappropriately use words such as first, second, next, and then (examples of
ordinal language) to convey the order of events; more experienced writers learn
to omit most ordinal language. Consider the following example:
Inappropriate Next, the extracts were combined, then they were reduced to
1 mL, and then they were frozen.
Inappropriate First, the extracts were combined; second, they were reduced
to 1 mL; and third, they were frozen.
Appropriate The extracts were combined, reduced to 1 mL, and frozen.
The corrected version is uncluttered and more concise. The use of ordinal language, although grammatically correct, detracts from the flow of the text. It is
unnecessary to state first or next because the sequencing of the procedure is
implied through the order in which the steps are presented. Another example is
presented in excerpt 3M (exercise 3.18). The authors describe a multistep cytotoxicity assay using very little ordinal language.
84
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Ordinal Language
Ordinal language indicates order or position in a series. Examples include the following:
■
first, second, third
■
next, then
Ordinal language should be used sparingly in journal articles.
Exercise 3.18
Read excerpt 3M and answer the following questions:
a. What details do the authors include regarding the preparation of butachlor
and incubation, harvesting, staining, and counting techniques?
b. How do the authors indicate the order of events? What did they do first,
second, third, etc.? To what extent was ordinal language used to convey this
sequence?
Excerpt 3M (adapted from Ou et al., 2000)
Cytotoxicity Assays. Cells were plated into 60 mm diameter dishes at several different densities (250–500 cells per dish, three dishes per density) to obtain more than
one set in which the number of surviving colonies ranged from 100 to 200. The cells
were treated with increasing doses (20–160 µM) of butachlor, previously dissolved in
ethanol, and the treated cells were left overnight. The next day, the old medium was
replaced with fresh medium. The cells were incubated for 10 days, harvested, fi xed with
methanol, and stained with Giemsa’s solution. Colonies containing more than 50 cells
per colony were counted as survivors, and survival rates for treatment groups relative to
the control were calculated. The concentrations of butachlor used to produce a survival
rate of >20% were used in further experiments.
Nonsynthetic procedures also require that authors express numbers and units
in conventional ways. Consider excerpts 3N and 3O, which describe two extraction procedures. Note the use of numbers in each excerpt.
Exercise 3.19
Read excerpts 3N and 3O. Pay particular attention to (1) the form of numbers
(numerical or word form) and (2) the formatting of units for time and measure (e.g., temperature, concentration, volume, area, and length). What do you
notice?
Writing the Methods Section
85
Excerpt 3N (adapted from Tateo and Bononi, 2004)
Extraction Procedure from Hot Chilli. The sample was finely ground using an
electric blender. Two grams were shaken for 20 min with 20 mL of ethanol (96%) and
stirred in an ultrasonic bath for 10 min. The extraction was repeated three times, each
time recovering the liquid phase after fi ltration on sodium sulfate anhydrous. The
extract, collected in a sealed fl ask, was concentrated under vacuum in a rotary evaporator to about 10 mL, transferred into a 25 mL volumetric flask, and diluted to volume
with ethanol (96%).
Excerpt 3O (adapted from Cabras et al., 2001)
Extraction Procedure from Powdery Stem Wood. A 0.1 g sample of R. speciosa
ground powdery wood was weighed in a 40 mL screw-capped tube, and 10 mL of chloroform was added. Tubes were placed in an ultrasonic bath for 15 min at a temperature
of 60 °C and then centrifuged for 5 min at 4500 rpm. A 1 mL aliquot was removed, and
organic solvent was dried under a nitrogen stream, taken up with 1 mL of mobile phase
(water/methanol, 75:25, v/v), and filtered with a 0.45 µm PTFE membrane fi lter. The
resulting solution was analyzed by HPLC.
About Numbers
■
Use numerals with units of time or measure (6 min, 5 g, 273 K).
■
Use numerals for numbers greater than nine (10 samples).
■
Use words for numbers less than 10 (nine samples), except for units of time or measure
(9 min).
Some exceptions:
■
Use all numerals in a series or range of values containing the number 10 or greater (e.g.,
5, 8, and 12 samples).
■
Use words for numbers that start a sentence, unless the number is part of a chemical
name (e.g., “Nineteen samples were analyzed.” “2-Butene was added.”).
Consult The ACS Style Guide for more details.
As you read excerpts 3N and 3O, you probably noticed that scientists most
often use the numerical form for numbers (e.g., 5) rather than the word form (e.g.,
five). Indeed, the numerical form is always used with units of time (e.g., s, h, min,
days, weeks, years) and measure (e.g., mL, cm, m3, g, K), unless the number starts
the sentence. Note, too, that there is a space between the number and the unit.
Incorrect
Correct
86
2mL 0.6cm 4.2ft
2 mL 0.6 cm 4.2 ft
0.015mg
0.015 mg
8K 180°C 180° C
8 K 180 °C
The Journal Article
To remember the space, treat units like words. You would write “twelve compounds” not “twelvecompounds”; hence, you would write “12 mL” not “12mL.”
A notable exception to this rule occurs with percentages; in this case, there is no
space between the number and the percent sign (%):
Incorrect
Correct
85 %
85%
eighty-five %
eighty-five%
Units of Measure
Measure is a general term that implies units of
■
volume (mL, cm3)
■
width or length (m, cm)
■
mass (g, mg)
■
temperature (°C, K)
■
concentration (g/mL, M)
Occasionally, the word form of a number is preferred. For example, words are
used for whole numbers less than 10 (e.g., nine flasks), except when the number
refers to time or measure (7 s, 5 mL). The numerical form is used for numbers
10 or greater (e.g., 10 flasks, 10 samples, 25 trees, 100 cm).
Incorrect
Correct
five cm
5 cm
6 fractions
six fractions
3 samples
three samples
thirteen sites
13 sites
Numbers and Units
See appendix A.
The word form is also used for numbers that start a sentence, unless the number is part of a chemical name. Whenever possible, however, rewrite the sentence
so that it does not begin with a number. Units are spelled out following a number
in word form and the plural verb is used (e.g., Ten milliliters were . . . ). A sentence
that begins with a spelled-out number reverts back to numerical form, when
appropriate, in the rest of the sentence. Consider the following examples:
Correct 2-Butene was purchased from Aldrich.
Correct Eleven hazelnut oils, 25 olive oils, and 7 other types of oil were
purchased. (Adapted from Ozen and Mauer, 2002)
Correct Two grams of NaCl were shaken for 20 min with 20 mL of ethanol.
Better NaCl (2 g) was shaken for 20 min with 20 mL of ethanol.
Writing the Methods Section
87
There are literally hundreds of units commonly used in chemistry; a few of
them are listed in table 3.2, along with their recommended abbreviations. A more
comprehensive listing is available in The ACS Style Guide. Some important rules
about using numbers and units are summarized below:
■
Abbreviate units of measure when they come after a numeral:
A degassed solution of 312 mg (1.39 mmol) . . .
■
Do not abbreviate units of measure that do not follow a numeral:
. . . several milligrams
Twenty percent . . .
■
Leave a space between a numeral and its unit of measure, unless the unit of
measure is a percent sign (%):
30 in.
80 ºC
600 g
95%
■
Do not add “s” to make an abbreviated unit of measure plural:
Incorrect
20 mgs
Correct
20 mg
■
Include a leading zero with numeric decimals:
Incorrect
.6 mg
Correct
0.6 mg
■
When using symbols such as <, >, and ±, include spaces between the
numbers and symbol if there are numbers on both sides of the symbol.
Also include spaces if the symbol falls in between a variable and a
number:
Incorrect
> 60 g
35±2%
P<0.05
Correct
<25 mL
80 ± 9%
ee > 99%
■
Use numerals in a series or range containing numbers 10 or greater to
maintain parallelism (even if smaller numbers would be written out in other
circumstances):
Incorrect
three, seven, and 14 samples
Correct
3, 7, and 14 samples
Correctly formatted abbreviations, numbers, and units are an essential part of
scientific writing. Formatting is the author’s responsibility; it is not the responsibility of a faculty mentor, peer reviewer, or journal editor. If you are not sure how
to format a number or word correctly, consult The ACS Style Guide and look for
instructions to authors in your journal of interest.
Exercise 3.20
Correct the following (incorrect) uses of numbers and units. Assume that these
numbers and units are not being used to start sentences.
7minutes
88
.15 mg
five percent
yield 12 hrs.
The Journal Article
10min.
15 mLs
0.175g
5 sec.
7 % recovery
100° C
13 hr.
300° K
Exercise 3.21
The paragraph below contains several errors in the use of numbers and units.
Identify at least 10 errors and correct them.
3-Benzyloxy-6-bromo-4-methoxyphenethyliminophosphorane. To a solution of
LAH (250mg) in THF (15ml) was added a solution of 3-benzyloxy-6-bromo-4-methoxyβ-nitrostyrene (500 mg, 1.37 mmol) in THF (15 mL), which was then boiled under
reflux for eight hours. Addition of several mL of water followed by extraction with ether
and drying the ether layer (K 2CO3) gave the corresponding phenethylamine, which was
purified by column chromatography on silica gel (hexane-CH 2Cl2, 6:4 v/v): yellow oil
(330 mg, 72 %); 1H NMR (400 MHz, CDCl3, δ): 7.33 (m, 6H), 6.77 (s, 1H), 5.05 (s, 2H),
4.62 (s, 2H), 3.82 (s, 3H), 2.94 (m, 4H). The amine (160 mg, .48 mmol) and triphenylphosphine (130 mg, .48 mmol) in 100 mgs of CCl4 and CH 2Cl2 (7 mL) were stirred
at 40° C for 72 hours under dry N2. (Adapted from Rodrigues et al., 2004)
We end our analysis of describing procedures (in submove 2) by examining ways
in which authors describe QA/QC procedures in their Methods sections. In general, there are two basic approaches. The first approach embeds the QA/QC procedures in the procedure itself. For example, in excerpt 3P, the authors describe
how they added a deuterated surrogate (recovery) standard to their samples at
the start of their procedure and how they added a deuterated internal standard
at the end of their procedure. The authors go on to describe the results of these
procedures in their Results section.
QA/QC Standards and Blanks
Blanks, spikes, surrogates, and internal standards are all terms associated with QA/QC
procedures. Collectively, they are used to measure sample contamination, analyte recovery,
and analyte relative abundance.
Excerpt 3P (from Peck and Hornbuckle, 2005)
Sample Extraction and Cleanup. The sample extraction method has been described
previously (27, 28). Prior to extraction, 100 µL of a d10-fluoranthene surrogate standard solution (0.82 ng/µL) was added to each sample. The XAD-2 resin was extracted
for 24 h in a Soxhlet apparatus with ~350 mL hexane/acetone (50/50 v/v). The extract
volume was then reduced to ~100 µL using rotary evaporation followed by evaporation
Writing the Methods Section
89
with nitrogen. Each sample extract was passed through a Pasteur pipet containing
~0.75 g 100–200 mesh Florisil with 4 mL ethyl acetate to provide cleanup as described
by Foreman et al. (8). After cleanup, the sample extract was reduced to ~100 µL with
nitrogen evaporation and 100 µL of an internal standard solution containing d10acenaphthene (2.5 ng/µL), d10-phenanthrene (2.4 ng/µL), and d10-pyrene (2.2 ng/µL).
In excerpts 3Q and 3R, the authors describe their QA/QC procedures in separate subsections, complete with their own subheadings (Method Performance
and Quality Assurance/Quality Control). Results of the QA/QC procedures
(e.g., relative standard deviation across replicate samples, recoveries, and accuracy) are commonly described in the Methods section, rather than in the Results
section.
Excerpt 3Q (adapted from Meijer et al., 2001)
Method Performance. A blank sample, prepared using the same procedure as for
the samples, was included with every five samples. PCB 28 and γ-HCH were the only
compounds detected in the blanks. Detection limits, calculated as mean blank +3 SD,
were typically 2.3–13.3 pg/µL = 0.02–0.12 ng/g soil. Results were not blank corrected.
Replicate analysis (the same soil sample extracted three times) was done for several
samples. The relative standard deviation (RSD) for replicate analysis was always less
than ±20% (n = 3). Analytical recoveries were monitored with the aid of two recovery
standards: mirex for F1 and δ-HCH for F2. The mean recovery for mirex was 100 ±
6% (range 89–115%); for δ-HCH, it was 80 ± 9% (range 62–94%). Data were not corrected for recoveries. Extraction procedures and recoveries of a standard containing all
target compounds were assessed by spiking four soil samples; recoveries ranged from
74 to 135%.
Excerpt 3R (adapted from Grundl et al., 2003)
Quality Assurance/Quality Control. QA/QC measures included field blanks,
solvent blanks, method blanks, matrix spikes, and surrogates. Percent recovery was
determined using three surrogate compounds (nitrobenzene-d5, 2-fluorobiphenyl,
4-terphenyl-d14) and matrix spikes (naphthalene, pyrene, benzo[ghi]perylene); the
recoveries ranged from 80 to 102%. Separate calibration models were built for each of
the 16 PAHs using internal standards (naphthalene-d 8, phenanthrene-d10, perylene-d12).
Validation was performed using a contaminated river sediment (SRM 1944) obtained
from NIST (Gaithersburg, MD); accuracy was <20% for each of the 16 analytes.
Describe Instrumentation
Authors must also describe the instrumentation or scientific apparatus that they
used in their work. (Note that ordinary equipment, e.g., a distillation apparatus
or a rotary evaporator, should not be described.) Instrumentation generally falls
into two categories: custom-built or commercial. Custom-built instrumentation
90
The Journal Article
includes novel or hand-built chambers, devices, or instruments. The first publication that describes a custom-built instrument offers the most detail and often
includes a diagram. Subsequent publications briefly highlight the essential features of the apparatus and refer the reader to the original article for more information. Excerpt 3S, for example, includes a diagram of a home-built sonic-spray
ionization (SSI) source used to optimize mass spectrometric conditions for generating amino acid clusters. When the authors of excerpt 3S make reference to
the same sonic-spray source in a second article (see the short excerpt below), the
authors refer back to the first article, rather than repeat a detailed description.
You’ll notice the superscript (40) that leads readers to the reference list at the end
of the article. The reference list contains the full citation of the original article in
which the SSI source is explained in more detail.
A home-built spray ion source,40 operable in both the sonic-spray ionization (SSI) and
electrospray ionization (ESI) modes, was used instead of the standard ESI source of the
Finnigan LCQ instrument. (From Takats et al., 2003b)
Plural of Apparatus
The word apparatus has two plural forms:
apparatus
apparatuses
The ACS Style Guide (3rd ed.) recommends the former as the preferred form.
Descriptions of Apparatus
The ACS Style Guide (3rd ed.) specifies that an apparatus should be described only if it is not
standard or not available commercially. With standard, commercially available apparatus,
stating a company name and model number in parentheses is appropriate and adequate.
More than likely you will need to describe a commercially available instrument
or standard piece of instrumentation in your Methods section. Several common
types of instrumentation (and their abbreviations) are listed in table 3.2; these
instruments are so common and standardized that no instructions or diagrams
are needed to explain how they work. It is necessary, however, to report the operational parameters under which an instrument was operated. Parameters are
selected and optimized for each particular application of an instrument and can
vary among users, even for the same instrument. Moreover, parameters affect the
outcome and reproducibility of an experiment; hence, they must be described.
Characteristic ways to report parameters have been developed for many types of
Writing the Methods Section
91
instruments. Excerpts 3I and 3K illustrate how to refer to a 1H NMR spectrometer.
Excerpts 3T–3V illustrate details that are typically included for FTIR and GC/MS
measurements.
Operational Parameters
The conditions (settings) under which a particular instrument is operated.
Exercise 3.22
With which of the following instruments should you include a diagram of the
instrumentation in a Methods section? Why?
a. a 1H NMR instrument (400 MHz)
b. a reflux apparatus
c. a Soxhlet extraction apparatus
d. a Nicolet 870 FTIR spectrometer with an attenuated total reflectance (ATR)
accessory
e. a new nozzle design for an ICP mass spectrometer
Excerpt 3S (adapted from Takats et al, 2003a)
Experimental Section
A sonic spray source was built following the Hirabayashi design but instead of an
aluminum orifice of 0.4 mm diameter, a coaxial fused-silica capillary with internal
diameter of 0.25 mm was used. A detailed cross-sectional view of the source is shown
in Figure 1 [see p. 93]. The smaller difference between the o.d. (0.2 mm) of the sample
capillary and the i.d. of gas capillary (0.25 mm) was expected to provide higher linear
gas velocities at similar mass flow rates. The source was operated at a nitrogen nebulizing gas pressure of 1.2 × 106 Pa. Liquid sample was introduced at a flow rate in the range
of 1–50 µL/min. Electrospray spectra were recorded using the same ion source operated
in a pneumatically assisted electrospray mode. The nebulizing gas pressure was 1.0 × 105
Pa, and the sample flow rate was 1–3 µL/min. A high voltage of 2.3–2.7 kV was applied
on the infusion syringe tip using a copper alligator clip. Experiments for the comparison
of two techniques (ESI and SSI) were carried out without changing source geometry and
instrumental settings, except for the spray high voltage and nebulizing gas pressure,
both of which were optimized.
Excerpt 3T (adapted from Kizil et al., 2002)
FTIR Measurements. FTIR spectra were recorded using a Nicolet model 870 spectrometer (Madison, WI) equipped with a deuterated triglycine sulfate (DTGS) detector.
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Figure 1. Schematic cross section of sonic spray ion source. Liquid sample is pneumatically
sprayed by the coaxial gas flow. The cross section of the gas flow in this source is restricted to
0.017 mm 2.
The sampling station was equipped with an overhead DRIFTS accessory. The sample
holder was used for the background spectra without KBr, and 256 coadded scans were
taken for each sample from 4000 to 400 cm–1 at a resolution of 16 cm–1. Single-beam
spectra of the samples were obtained, and corrected against the background spectrum of
the sample holder, to present the spectra in absorbance units. Spectra were collected in
duplicate and used for multivariate analysis.
FT-Raman measurements. FT-Raman spectra were obtained using a Nicolet 870
spectrometer with the Raman module 32B (Madison, WI) and Nd:YAG laser operating at 1064 nm with a maximum power of 2 W. The system was equipped with an
indium-gallium arsenide (InGaAs) detector, XT-KBr beam-splitter with 180° reflective
optics, and a fully motorized sample position adjustment feature. A laser output power
of 0.77 W was used, which was low enough to prevent possible laser-induced sample
damage yet provided a high signal-to-noise ratio. Data were collected at 16 cm–1 resolution with 256 scans. Spectra were obtained in the Raman shift range between 400 and
4000 cm–1. The system was operated with the OMNIC 5.1 software, and experiments
were done in duplicate.
FTIR What?
Beginning writers often say “FTIR was used,” but this is incorrect. FTIR is the abbreviation
for “Fourier transform infrared” (all serving as adjectives). Thus, you need to include a noun
Writing the Methods Section
93
following FTIR, such as the following: FTIR analysis, FTIR measurements, FTIR spectroscopy,
an FTIR spectrum, or several FTIR spectra.
Excerpt 3U (adapted from Llompart et al., 2001)
Chromatographic Conditions. GC/MS–MS analyses were performed on a Varian
3800 gas chromatograph (Varian Chromatography Systems, Walnut Creek, CA)
equipped with a 1079 split/splitless injector and a ion trap spectrometer (Varian Saturn
2000, Varian Chromatography Systems) with a waveboard for MS–MS analysis. The system was operated by Saturn GC/MS WorkStation v5.4 software. The MS–MS detection
method was adapted from reference.29 PCBs were separated on a 25 m length × 0.32 mm
i.d., CPSil-8 column coated with a 0.25-µm film. The GC oven temperature program
was as follows: 90 °C hold 2 min, ramp 30 °C/min to 170 °C, hold for 10 min, rate 3 °C/
min to 250 °C, rate 20 °C/min to a final temperature of 280 °C, and hold for 5 min.
Helium was employed as the carrier gas, with a constant column flow of 1.0 mL/min.
The injector was programmed to return to the split mode after 2 min from the beginning
of a run. Split flow was set at 50 mL/min. The injector temperature was held constant at
270 °C. Trap temperatures, manifold temperatures, and transfer line temperatures were
250, 50, and 280 °C, respectively.
Excerpt 3V (adapted from Pelander et al., 2003)
LC/TOFMS. The liquid chromatograph was an Agilent (Waldbronn, Germany)
1100 series system consisting of vacuum degasser, autosampler, binary pump, column
oven, and diode array detector. Separation was performed in gradient mode with a
Phenomenex (Torrance, CA) Luna C-18(2) 100 × 2 mm (3 µm) column and a 4 × 2 mm
precolumn. The column oven was kept at 40 °C. Eluent components were 5 mM
ammonium acetate in 0.1% formic acid and acetonitrile. Flow rate was 0.3 mL/min. The
proportion of acetonitrile was increased from 10 to 40% in 10 min, to 75% in 13.50 min,
to 80% in 16 min, and held at 80% for 3 min. Post-time was 5 min, and the injection
volume was 10 µL.
The mass analyzer was an Applied Biosystems (Framingham, MA) Mariner TOF
mass spectrometer equipped with a PE Sciex (Concord, ON, Canada) TurboIon Spray
source and a 10-port switching valve. The instrument was operated in the positive ion
mode. The eluent flow was carried to the ion source without splitting. The nebulizer
gas (N2) flow was 0.7 L/min, the curtain gas (N2) flow 1.2 L/min, and the heater gas
(N2) flow 8 L/min. The spray tip potential of the ion source was 5.5 kV, and the heater
temperature was 350 °C. Interface settings were as follows: nozzle potential 70 V, quadrupole rf voltage 800 V, and quadrupole temperature 140 °C. Skimmer 1 potential,
quadrupole dc potential, deflection voltage, and Einzel lens potential varied depending
on the daily tuning of the instrument. Analyzer settings were as follows: push pulse
potential 492 V, pull pulse potential 225 V, acceleration potential 4.0 kV, reflector
potential 1.55 kV, and detector voltage 1.9 kV. Pull bias potential varied depending on
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daily tuning. Spectrum acquisition time was 2 s, and a m/z range from 100 to 750 was
recorded.
Exercise 3.23
Consider excerpts 3T–3V. What operational parameters should you report when
FTIR spectroscopy is used in your research? What parameters should you include
when GC is used in your research? (If unfamiliar with these techniques, ask your
instructor what these parameters mean.)
Exercise 3.24
Consider the following sentence: “Samples were analyzed using UV–vis.” Explain
why such a sentence is inappropriate in a journal article, even if the instrumental
parameters are specified in subsequent sentences. Rewrite the sentence so that it
is appropriate for inclusion in a journal article.
Exercise 3.25
Find three articles that describe a single instrument that you have used. Compare
the parameters reported in each article.
3C Writing on Your Own: Describe Experimental Methods
Procedures. Write the procedures section of your Methods section. Begin by creating
an outline or flow chart that lists the steps that you followed in a given procedure. Cross
out steps that are too basic for an expert audience. Organize the remaining steps into a
concisely written paragraph, using the sequencing of your sentences to convey the order
followed in your experiment. If more than one procedure was used, repeat this process as
needed. Follow standard conventions for expressing numbers and units.
Instrumentation. Write the instrumentation section of your Methods section. When
appropriate, be sure to include vendors, model numbers, and operating parameters. Use
the literature to determine the operational parameters that you should include. Be sure to
use parentheses appropriately.
Move 3: Describe Numerical Methods
The final move of the Methods section involves the description of statistical, computational, or other mathematical methods used to derive or analyze data. This
move is required only if numerical methods were part of the work. Excerpts 3W
Writing the Methods Section
95
and 3X demonstrate how some common types of statistical methods, including
analysis of variance (ANOVA), are described. Once again, subheadings are used
to guide the reader’s attention to this information. Note that when specialized
statistical software is used, the name and version number of the software package
are reported. Important statistical parameters that affect the outcome of the statistical test (e.g., significance level) may also be reported, although these parameters
may also be reported in the Results section. Note that routine software such as
Microsoft Word or Excel should not be reported in this section (or anywhere else
in the journal article).
Excerpt 3W (from Ye et al., 2000)
Statistical Analysis. Statistical analyses (two-way ANOVA) were performed by using
the Statistical Analysis System (SAS, 1990). Means were compared by the least significant difference (LSD) test at α = 0.05.
Excerpt 3X (from Besser et al., 2004)
Statistical Analysis. Analysis of variance (ANOVA) of toxicity data was conducted
using SAS/STAT software (version 8.2; SAS Institute, Cary, NC). All toxicity data were
transformed (square root, log, or rank) before ANOVA. Comparisons among multiple
treatment means were made by Fisher’s LSD procedure, and differences between individual treatments and controls were determined by one-tailed Dunnett’s or Wilcoxon
tests. Statements of statistical significance refer to a probability of type I error of 5% or
less (p ≤ 0.05). Median lethal concentrations (LC50) were determined by the Trimmed
Spearman-Karber method using TOXSTAT software (version 3.5; Lincoln Software
Associates, Bisbee, AZ).
In excerpt 3Y, the authors refer to computational results performed with the
Gaussian suite of programs, a computational package used to calculate molecular
ab initio or semiempirical electronic structure theory. Computational parameters
(e.g., the basis set and level of theory) are included in the description. Do not
worry if you do not understand the content of excerpt 3Y; the language is intended
for chemists with a computational or theoretical background.
Ab initio vs. Semiempirical
The Latin term “ab initio” means “from the beginning” or “from first principles.” Ab initio
calculations involve no experimental (empirical) data; they are derived solely from theory.
(Note that ab initio should not be italicized or used with quotation marks.)
Semiempirical calculations combine both empirical (experimental) and
nonempirical data.
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Excerpt 3Y (from Kuwata et al., 2005)
II. Theoretical Methods
A. Quantum Chemistry Calculations. All electronic structure calculations were
performed with the Gaussian 03 suite of programs.31 The geometry, energy, and harmonic vibrational frequencies of each stationary point considered here were determined
initially using the B3LYP functional32,33 and the 6–31G(d,p) basis set.34,35 Each reported
minimum has all real frequencies, and each reported transition structure has one imaginary frequency. We determined the minima associated with each transition structure by
animation of the imaginary frequency and, if necessary, with intrinsic reaction coordinate (IRC) calculations.36,37
3D Writing on Your Own: Describe Numerical Methods
If appropriate, write the numerical methods subsection of your Methods section.
Depending on the type and extent of statistical, computational, or theoretical methods used, you may want to create a new subheading (e.g., Statistical Methods or
Theoretical Methods) or simply add this information to the end of your experimental
procedures.
If you are writing a theoretical paper, this section will be the bulk of your Methods
section. Be sure to include the brand names and versions of specialized software packages
used to analyze your data.
Part 2: Analyzing Writing across the Methods Section
Two writing conventions apply to the Methods section as a whole: the use of
tense (past or present) and voice (passive or active). Past tense and passive voice
predominate in the Methods section; however, in some cases, present tense and/
or active voice are also used. Like other writing conventions, the proper use of
tense and voice reveals authors’ familiarity with the expectations of the field, their
objectivity, and more expert-like writing abilities.
Past and Present Tense
The Methods section is largely written in the past tense. In general, the Methods
section describes work that was done in the past, making the past tense the appropriate choice. This is different from a lab manual, which gives a set of instructions
in the present tense.
Lab manual Stir the mixture. Heat to reflux.
Journal article The mixture was stirred and heated to reflux.
Writing the Methods Section
97
Although the Methods section is overwhelmingly written in the past tense, there
are few correct instances of present tense. The general rule of thumb for deciding
when to use past or present tense in the Methods section (and elsewhere in the
journal article) is as follows:
Work was done in the past; knowledge exists in the present.
Work done in the past is described using past-tense verbs (e.g., analyzed,
built, heated, investigated, isolated, measured, performed, synthesized, tested).
Knowledge that exists in the present (and presumably into the future) is described
using present-tense verbs (e.g., contains, defines, describes, explains, implies, is
expected to, provides, suggests). Present tense is also used to describe fi xed features of a custom-built instrument (e.g., length and width). Consider the following
examples. In each case, the past tense describes actions taken by the researchers
that led to their results; the present tense describes information that is expected
to be true over time.
Past tense
The water was triply distilled.
Present tense Triply distilled water contains less than 1 ppb of the impurity.
Past tense
Height measurements were taken using a nanoscope.
Present tense Height data provide topographical information.
Past tense
The probe was modeled after work described elsewhere (4).
Present tense The probe projects through the tee into the main chamber.
Past tense
Helium gas was used to purge the chamber.
Present tense The outer diameter of the chamber measures 10 cm.
Exercise 3.26
Each of the following passages contains a present- and past-tense verb choice. For
each italicized pair, select the correct verb tense:
a. Triply distilled water has/had a conductivity and surface tension lying within
experimental error of the literature values for ultrapure water. (Adapted from
Quickenden et al., 1996)
b. Phase data, which measure/measured the phase shift in the cantilever oscillation, are/were taken with an AFM operated in tapping mode. (Adapted from
Clancy et al., 2000)
c. The main body of the probe system is/was a stainless steel tee. (Adapted from
Van Berkel et al., 2002)
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d. The tests in this study were/are conducted in TCE-contaminated groundwater
in two distinct water-bearing zones, the A-zone and the C-zone. The A-zone
was/is an unconfined shallow layer composed mainly of placed fill over Bay
Mud. (Adapted from Hageman et al., 2001)
e. This peptide was/is chosen because it was/is predicted to form a loop structure on the surface of the folded protein. (Adapted from Stockton et al., 2003)
f. The lower spinning rate was/is chosen because higher rates routinely
interfere/interfered with the cross polarization process. (Adapted from
Vaisman et al., 2000)
Passive and Active Voice
The Methods section is also written largely in passive voice. Passive voice is most
often combined with past tense:
Inappropriate
Appropriate
We heat the mixture to 80 °C.
[present tense, active voice]
We heated the mixture to 80 °C. [past tense, active voice]
The mixture is heated to 80 °C. [present tense, passive voice]
The mixture was heated to 80 °C. [past tense, passive voice]
Frequency (per 500 words)
You may have been taught in other writing courses not to use passive voice
because it is considered “weak.” However, passive voice, when used appropriately,
strengthens writing in chemistry journal articles (and other scientific genres).
Figure 3.3 shows the frequency of passive voice in each section of a chemistry journal article. Note that passive voice is used in all sections, but it is most
common in the Methods section.
20
15
10
5
0
Abstract
Introduction
Methods
Results &
Discussion
Section
Figure 3.3 Frequencies of passive voice (expressed as the number of passive verbs per
500 words) in sections of chemistry journal articles, determined through a computerbased analysis of 60 journal articles (approximately 300,000 words).
Writing the Methods Section
99
Table 3.4 Passive-voice–past-tense combinations commonly used in Methods
sections.a
was added
was determined
was maintained
was refluxed
was allowed
was dissolved
was performed
was removed
was assigned
was dried
was poured
was separated
was carried out
was evaporated
was prepared
was stirred
was collected
was extracted
was purified
was treated
was concentrated
was filtered
was quenched
was used
was cooled
was heated
was recorded
was washed
a. These passive-voice–past-tense combinations were identified through a computer-based
analysis of passive voice in the Methods sections of 60 published chemistry research articles.
Passive voice is preferred because it sounds more objective. Passive voice essentially removes the human subject (i.e., the scientist) from the sentence so that the
focus of the sentence is the object that was acted on.
Active We added solid Se (0.030 g) to the pale orange solution.
Passive To the pale orange solution was added solid Se (0.030 g).
Active We stirred the mixture for 10 min at room temperature.
Passive The mixture was stirred for 10 min at room temperature.
A list of passive-voice, past-tense combinations commonly used in Methods sections is provided in table 3.4.
Joining Sentences in Passive Voice
When you join two sentences that are in past-tense passive voice, each subject must have
a verb that is preceded by “was” or “were.”
Incorrect The eluant was added to the column, and the samples collected in 10 mL
increments.
Correct The eluant was added to the column, and the samples were collected in 10 mL
increments.
Passive Voice
See appendix A.
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Exercise 3.27
Rewrite these sentences so that they are more appropriate for the Methods section
of a journal article; use passive voice and past tense:
a. We recrystallized the product from ethanol in a fume hood.
b. We measured the temperature with a K-type thermocouple located just above
the catalyst bed.
c. Filter the precipitate. Wash three times with 10 mL of ethanol each time.
d. Add chlorosulfonic acid (0.350 mL) dropwise to a flask containing acetic acid
in an ice bath.
e. We used a Nicolet model 590 FTIR spectrometer to analyze the water-ice
films.
f. We collected all of our samples in amber glass bottles with Teflon-lined caps
(EPA level 1, 33 mm, VWR).
g. We used the Box-Hunter program run under MAPLE computer algebra software (v. 5, Waterloo Maple, Inc.).
3E Writing on Your Own: Practice Peer Review
Before you engage in authentic peer review (when a classmate reviews your Methods
section and you review a classmate’s Methods section), practice the peer-review
process. Imagine that a classmate or colleague has asked you for feedback on a draft
of a Methods section. See “Peer Review Practice: Methods Section” at the end of the
chapter for a copy of the draft, background information, and instructions for completing the task.
3F Writing on Your Own: Fine-Tune Your Methods Section
By now, you likely have a solid draft of your Methods section, including a description
of materials, experimental methods, and numerical methods (if applicable); hence, it
is time to revise and edit your Methods section as a whole. We recommend that you
reread and edit your work, focusing on each of the following areas and using chapter 18
to guide you.
1. Audience and conciseness: Are you writing for an expert audience, leaving out unnecessary details? Try to find at least three sentences that can be written more clearly and
concisely. Check for information that should be placed inside parentheses.
2. Organization of text: Check your overall organizational structure. Did you follow
the move structure in figure 3.1 and include appropriate subheadings? Do your
Writing the Methods Section
101
experimental procedures clearly convey the order followed in your work (without using
ordinal language)?
3. Writing conventions: Check to be sure that you have used voice (mostly passive) and
tense (mostly past tense) correctly. Check your formatting of units and numbers, use of
abbreviations and acronyms, and capitalization of compounds and vendors.
4. Grammar and mechanics: Check for typos and errors in spelling, subject–verb agreement, punctuation, and word usage (e.g., effect vs. affect, data).
5. Science content: Have you correctly conveyed the science in your work? Have you used
words and units correctly? If asked, could you define all of the words that you have
used? Do you understand, in principle, how the instruments described in your methods
section work?
After thoroughly reviewing and revising your own work, it is common practice to
have your work reviewed by a peer or colleague. A “new set of eyes” will pick up
mistakes that you can no longer see because you are too familiar with your own
writing. To facilitate the peer-review process, use the Peer Review Memo form
(on the Write Like a Chemist Web site) to assist you and your peer reviewer. After
your paper has been reviewed (and you have reviewed another’s paper), consult
the Peer Review Memo given to you by your partner to make final changes in your
Methods section.
Finalizing Your Written Work
See chapter 18.
Chapter Review
Check your understanding of what you’ve learned in this chapter by defi ning
each of the following terms for a friend or colleague who is new to the field:
abbreviation
ab initio
acronym
active voice
numerical methods
operational parameters
ordinal language
passive voice
QA/QC
semiempirical
As a review, try explaining the following to a friend or colleague who has not yet
tried to write a Methods section for a journal article:
102
■
Main purpose of a Methods section
■
Three typical moves of a Methods section
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■
Capitalization conventions for a Methods section
■
Guidelines for spelling out abbreviations in a Methods section
■
Guidelines for the inclusion of an illustration of an apparatus in a Methods
section
■
Guidelines for conveying the order of events in a Methods section
■
Appropriate use of numbers and units in a Methods section
■
Use of tense (past/present) and voice (active/passive) in a Methods section
■
Reporting of quality control results in a Methods section versus a Results
section
Additional Exercises
Exercise 3.28
Look back at exercise 3.1. Complete column 2 by placing a check next to items
that you think should be included in a Methods section. Compare your answers
with those in column 1. How have your ideas about Methods sections changed
since the beginning of the chapter?
Exercise 3.29
Reread excerpt 3A and reexamine your answers to exercise 3.2. How would you
modify your responses so that they are more accurate? Do you notice anything
now that you did not notice earlier?
Exercise 3.30
Using the excerpts in this chapter as a guide, what are the correct abbreviations
for the following units?
boiling point
centimeters
grams
hours
meters
micrograms
micrometers
Writing the Methods Section
milligrams
milliliters
millimeters
millimoles
minutes
moles
nanometers
103
Exercise 3.31
Rewrite the following lab manual passage so that it is appropriate for the Methods
section of a journal article:
Clean the Erlenmeyer fl ask with deionized water and let it dry. Add 14.3 grams (or
0.25 moles) of activated zinc dust and 80 mL of HMPA to the dried flask. Stir to mix.
Next, add 32 mL of chlorotrimethylsilane (equivalent to 0.24 mol). Stir the mixture for
90 minutes at room temperature. Cool the mixture on ice for 20 minutes.
Exercise 3.32
The passage below is the Methods section from a student paper. Considering what
you have learned in this chapter, improve the paper through revision.
Methods
General Methods. Purity was determined using 1H-NMR, IR, and TLC. Thin-layer
chromatography was performed on a silica gel plate and developed in dichloromethane.
Preparation of isopropyl-MgBr (2). To ensure anhydrous conditions, we flame-dried
the flask. Next, Mg (14.81 mmol) and three crystals of I2 were added and heated until
I2 vapor filled the flask. Once the fl ask cooled to room temperature, 2-bromopropane
1 (1.13mL) in anhydrous diethyl ether (10 mL) was added, refluxed for 15 m at 40° C,
then cooled to room temperature.
Preparation of 1-(4-methoxyphenyl)-2-methylpropan-1-ol (4). 4-methoxybenzaldehyde(p-anisaldehyde) 3 (4.99 mmol) in anhydrous diethyl ether (10 mL) was
gradually added to the Grignard reagent (0.5 mL increments), refluxed for 10 m at 40° C,
and poured over ice water (50 mL). 1M H 3PO4 was gradually added until the mixture
became acidic. Then we rinsed the extracted ether layers with 5% aqueous NaOH
(10 mL) and saturated NaCl (10 mL). It was dried with anhydrous magnesium sulfate
and ether was extracted from the product using distillation. R f = 0.45 (silica); IR (cm–1)
3240 cm–1 (R-OH); 1H NMR (400 MHz, CDCl3, δ): 0.88 (d, J = 6.58 Hz, 3H), 0.91 (d, J =
6.58 Hz, 3H), 1.99 (s, 3H), 5.21 (m, 1H), 2.08 (s, 1H), 3.76 (s, 3H), 4.45 (d, J = 7.64 Hz,
1H), 6.85 (d, J = 8.18 Hz, 2H), 7.39 (d, J = 8.18 Hz, 2H).
Exercise 3.33
Rewrite the following wordy passages. Make them sufficiently concise so that they
are appropriate for journal article Methods sections. Do not get distracted by the
science; you do not need to understand the science fully to improve the passages
with the conciseness techniques presented in chapter 2. Hints and word-count
goals are provided for each passage to focus your efforts.
a. Prior to the reaction being started, the solution was evacuated to the point
that gas evolution stopped and purged for a period of 10 min with Ar to free
it from O2. (32 words)
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(Hint: Avoid using language that conveys the sequencing of steps and use
nominalizations when appropriate. Goal: 11–12 words)
b. Sample Preparation. Two sets of coal samples, each prepared by mixing
0.5 g of liquid with 1.0 g of Pittsburgh No. 8 coal (used as received), were
prepared. The coal used was 100-mesh and used as received, after which the
liquid was added to the coal in drops. The resulting sample was then mixed
by shaking. The samples that were used for the WAXRS experiments were
then stored in 20 mL scintillation vials with screw-top caps. A portion of the
sample was removed 1 day after its preparation and subsequently used as the
subject of each wide-angle X-ray scattering experiment. (Adapted from Wertz
and Smith, 2003) (103 words)
(Hint: Combine several short sentences into fewer, more complex sentences,
delete redundant or unnecessary information for an expert audience, and use
parentheses to present information about materials and to define abbreviations. Goal: 50 words)
c. Purification. E. coli BL21 (DE3) containing the plasmid pMB1912 (dadXPA)
(6) was grown at 37 °C in Luria broth containing ampicillin (100 µg/mL).
At OD600 = 0.5, IPTG (0.5 mM) was added, and afterwards cells were grown
overnight at a temperature of 30 °C. Cell pellets were resuspended in 50 mM
Tris, pH = 7.6, 0.5 mM PLP; next, 150 µg of purified Serratia marcescens
nuclease was added. Cells were lysed using a Spectronic French Press at
16 000 psi, and cell debris was removed by centrifugation. (NH4)2SO4 20
and 60% cuts were done, and following the final cut, the protein pellet
was dialyzed against 20 mM Tris, pH = 7.6 and filtered through a 0.45 µm
syringe filter. After this preparation, the material was loaded on a Pharmacia
Q-Sepharose HP column and eluted with a 0–0.5 M NaCl gradient. (Adapted
from LeMagueres et al., 2003) (139 words)
(Hint: Avoid using sequencing language and use parentheses where appropriate. Goal: 113 words)
Exercise 3.34
Rewrite the following sentences using the conventional language of a synthesis
paper. Try to do it on your own first. Then review the excerpts, the Describing a
Synthesis pointer (p. 82) and the three “formulas” (p. 83) to assist you with your
final fine-tuning of these sentences.
a. To a beaker, which contained 30 mL of ether and 103.1 g benzonitrile
(1.00 mol), was added 68.1 g (0.50 mol) zinc chloride.
b. A solution of water saturated with NaCl was used to wash the impure product that was produced at the end of the reaction.
c. The solution was heated until it began to boil and recondense. After 10 min
of boiling, it was allowed to cool to the surrounding temperature.
Writing the Methods Section
105
d. The top (water-insoluble) layer was washed with a saturated solution of
sodium chloride in water (2 × 25 mL).
Exercise 3.35
Reflect on what you have learned about writing a Methods section for a journal
article. Select one of the reflection tasks below and write a thoughtful and thorough response:
a. Reflect on the differences among the ways in which methods are reported in
lab manuals, lab reports, and journal articles.
■
■
■
What are the predominant differences between the ways in which methods are reported in lab manuals, lab reports, and journal articles?
Why do you think that the formats are so different?
What purposes do the different formats serve?
b. Reflect on the numerous writing conventions that are typical of a journal
article Methods section.
■
■
■
■
Which writing conventions are relatively new to you?
Which writing conventions have you used before?
Which writing conventions do you have to make an effort to remember?
Why do you think expert readers and writers in chemistry take these
conventions so seriously?
c. Reflect on the numerous excerpts that you have read in this chapter. Excerpts
3A–3Y come from different journals and report on different types of chemical
research, but they have all been written for expert audiences.
■
■
■
■
What features do the excerpts have in common? Give specific examples in
your response.
What features of this professional writing are most impressive to you?
What aspects of this writing do you think will be easiest to learn to use?
Hardest to learn to use?
How might the reading of the chemical literature help you with your own
writing?
d. Reflect on the ways in which tense and voice are used in a Methods section.
■
■
■
■
106
What rules have you created for yourself to remember when to use the
present tense and past tense in a Methods section?
What rules have you created for yourself to remember when to use active
voice and when to use passive voice in a Methods section?
How can the proper use of tense and voice help you achieve objectivity in
your writing?
In what ways can the improper use of tense and voice cause miscommunication with your readers?
The Journal Article
Peer Review Practice: Methods Section
Imagine that a friend has asked you to review a draft of a Methods section
for a paper to be submitted to the Journal of Agricultural and Food Chemistry.
Unfortunately, your friend has not had the benefit of a chemistry writing course;
hence, a few writing tips would be appreciated. The project involves the identification of odor-active compounds in 19 California chardonnay wines. The steps
involved in the study are as follows:
1. extracting the volatiles from the wine
2. concentrating the extracts (using distillation)
3. fractionating the concentrated extracts into three fractions (using silica gel
chromatography)
4. screening “oral-active” fractions in the wine (using GC-olfactometry)
5. identifying/quantifying the compounds in the “oral-active” fractions (using
GC-MS)
The first three steps are straightforward (extracting, concentrating, and fractionating the volatiles in the wine). In the fourth step, when the effluent comes off the
GC column, half of it goes to a “sniffing port” (GC-olfactometry, step 4) and half
of it goes to a mass spectrometer (GC-MS, step 5). Judges at the “sniffi ng port” are
asked to indicate if the fraction is “odor-active” or not. If it is, they give a verbal
description of the smell (using such words as glue, buttery, creamy, plastic, green
grass, fruity, musty, and many others). The odor-active compounds are then identified and quantified by GC-MS. Eighty-one compounds were shown to be odoractive; of these, 74 were quantified and 61 were tentatively identified.
Using parts 2 and 3 of the Peer Review Memo form on the Write Like a Chemist
Web site, provide feedback on the Materials and Methods draft. Give specific
suggestions that can be used to improve the written work. (The Methods section
below is adapted from an original source, cited in the Instructor’s Answer Key.)
Materials and Methods
1 Purchased from EM Science, a division of EM Industries, Inc (New Jersey):
2
Diethyl Ether
3
Pentane
4
Silica Gel 60 (particle size 0.063–0.200 mm, 70–230 mesh)
5 Sigma-Aldrich Chemical Co. (St. Louis, MO):
6
Trichlorofluoromethane (Freon 11)
7
Absolute Ethanol
8 Compounds used as internal standards (IS)
9
Methyl Octanoate
10
2-Methyl-1-Pentanol
Writing the Methods Section
107
11
12
3-Methyl-3-Hydroxy-2-Butanone
GC-O/GC-MS Operating Parameters
13
14
15
16
17
18
19
20
21
Model:
Injector:
Column type:
Column size:
Detector:
Inlet temp:
Carrier gas:
Program:
Hewlett-Packard (HP) GC model 6890, Palo Alto, CA
Split/splitless (operated in splitless time of 1 min.)
DB-WAX bonded fused capillary column
30 m x 0.25 mm i.d., film thickness—0.25 µm
MS 6890 series mas selective dector, HP, Palo Alto, CA
220 ºC
Helium gas at flow of 1.3 ML/min.
Oven temperature held at 40 ºC for 4 min., ramped at 4 ºC/min. to
185 ºC, held for 20 min.
22 Nineteen 1997 Californian Chardonnay wines were analyzed in 2000, all of which had
23 been profiled by descriptive analysis (DA) 6–10 months before this study (17). All wines
24 were held at 10 ºC during the studies.
25
All glassware was washed thoroughly with liquid soap and distilled water and
26 allowed to dry before use. The IS stock solution was prepared by adding 5 μg of each
27 internal standard to 100 ML of Absolute Ethanol.
28
Volatiles were extracted using a modification of a procedure described elsewhere (18).
29 Before extraction, 150 ML of wine was carefully poured into a 500 ML round-bottom
30 flask. First, 45 g of Sodium Chloride (NaCl) and 3 ML of IS stock solution were added
31 to the wine, which was then extracted 3 times with 50 ML of Trichlorofluoromethane
32 (Freon 11) using a liquid-liquid extractor at 28–30 ºC. Next, the extract was concen33 trated to ~2 ML by distilling off the solvent on a Vigreux column (40 × 2 cm). The
34 solvent was further removed under a purified Nitrogen stream until the volume was
35 reduced to 1 ML. We fractionated the aroma extracts by Silica Gel chromatography to
36 provide better GC resolution, using a modification of Guth’s method (19). The Freon
37 extract (1 ML) was placed in a glass column (30 × 1.9 cm i.d.) packed with Silica Gel
38 60. The sample was fractionated by elution with 200 ML of Pentane and Diethyl Ether
39 (Fraction 1, 85/15; Fraction 2, 70/30) and 200 ML of Diethyl Ether (Fraction 3). Finally,
40 the eluates were dried over Sodium Sulfate overnight and concentrated to a fi nal volume
41 of 1 ML, as described above, and stored at -5 ºC for subsequent analyses.
42
The recovery of internal standards after sample preparation (extraction, fraction43 ation, and GC analysis) was evaluated for 5 wines (JL, CDB-C, CAL, DEL and SH).
44 Recovery ranged from 82% for Methyl Octanoate in fraction 1 to 73% for 2-Methyl-145 Pentanol in fraction 2 and to 61% for 3-Methyl-3-Hydroxy-2-Butanone in fraction 3.
46 Reproducibility of the sample preparation method was examined for 1 wine (SH). A
47 two-way analysis of variance for each peak showed no significant differences due to
48 extraction or injection.
49
A 1-μL sample of each concentrated wine fraction was analyzed by gas chromotog50 raphy-olfactometry (GC-O). GC operating parameters are listed above. As the effluent
51 came off the column, it was split 50:50 between a sniffi ng port (Gerstel, Germany) for
52 GC-O analysis and a mass spectrometer for GC-MS analysis (see below). The sniffing
53 port was held at 250 ºC to prevent any condensation of volatile compounds. Humidified
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The Journal Article
54 air was added at 100 ML/min. in the sniffi ng cone to reduce fatigue and drying of the
55 judges’ nasal passages. For determination of odor-active (OA) compounds, four judges
56 who had previous experience with GC-O were used. Assessors were seated in front of
57 the sniffing port and asked to smell the effluent off the column. An “olfactory button”
58 (Gerstel, Germany) was depressed when an aroma was detected. Judges also gave verbal
59 descriptions of perceived odors that the experimenter recorded.
60
Fractions identified as odor-active were analyzed using GC-MS. The column and
61 operating conditions were the same as those used for GC-O. The detector was a mass
62 spectrometer (MS 6890 series mass selective detector, Hewlett Packard, Palo Alto, CA).
63 Mass spectrum were taken over the m/z range 45–300. The total ion chromatogram
64 (TIC) acquired by GC-MS was used for peak area integration. HP MS chemstation soft65 ware G1701BA ver.B.01.00 was used for data acquisition.
66
We tentatively identified the oral-active compounds (screened by the GC-O) by
67 comparison of the Kovats retention index (KI) (21) and the MS fragmentation pat68 tern with those of reference compounds or with mass spectra in the Wiley 275 library
69 and previously reported Kovats retention indices. The Kovats retention indices (KI) of
70 unknown compounds were determined by injection of the sample with a homologous
71 series of alkanes (C6 -C28).
72
The relative concentrations of the odor-active volatiles in all 19 wines were deter73 mined by GC-MS (TIC) by comparison with concentrations of internal standards,
74 assuming a response factor of 1. Methyl Octanoate, 2-Methyl-1-Pentanol, and 3-Methyl75 3-Hydroxy-2-Butanone were used as the internal standards for fractions 1, 2, and 3,
76 respectively.
77
GC data were first entered into an Excel (Microsoft) spreadsheet and later
78 imported into statistical analysis software.Analyses of variance were run on the GC
79 data using PROC GLM on Statistical Analysis Systems (SAS) for Windows, version 6.12
80 (Cary, NC).
Writing the Methods Section
109
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4
Writing the Results Section
All sections of a journal article lead up to or away from the
results section, and the results section may retain its value long
after the methods and conclusions have become obsolete.
—Paradis and Zimmerman (1997)
This chapter focuses on the Results section of the journal article. The Results
section makes use of both text and graphics to highlight the essential findings of a
study and to tell the story of scientific discovery. In this chapter we focus on writing the text; we refer you to chapter 16 for information on formatting graphics
(e.g., tables and figures). After reading this chapter (and chapter 16), you should
be able to do the following:
■
Distinguish between the description and interpretation of data
■
Organize and present your results in a clear, logical manner
■
Refer appropriately to a figure or graph in the text
■
Use appropriate tense, voice, and word choice
■
Prepare a properly formatted figure and table
Graphics
We use the term graphics to refer to figures, tables, and schemes.
Figures and tables are used to display, clarify, and summarize results, helping readers
comprehend data more quickly.
Schemes are used to illustrate mechanisms (see chapter 5).
Formatting Graphics
Instructions for formatting figures, tables, and schemes are presented in chapter 16.
Consult chapter 16 as you work through this chapter.
As you work through the chapter, you will write a Results section for your own
paper. The Writing on Your Own tasks throughout the chapter will guide you
step by step as you do the following:
4A Read the literature and review your results
4B Organize your results
4C Prepare figures and/or tables
4D Tell the story of scientific discovery
4E Practice peer review
4F Fine-tune your Results section
The purpose of a Results section (the third section in the standard IMRD format) is to present the most essential data collected during a research project. A
well-written Results section guides the reader’s attention back and forth between
text and graphics while highlighting important features of the data and telling
the story of scientific discovery. Months (possibly years) of accumulated knowledge and wisdom, and countless pages of data, are distilled into only a few
pages; hence, only the essential threads of the story are included in the Results
section.
In many journal articles, the Results section is actually a combined Results
and Discussion (R&D) section. Combined R&D sections are preferred by many
scientists who want to present and discuss results in an unbroken chain of
thought. The combination is often more concise because less time is spent
reminding the reader which results are being discussed. Combined R&D
sections are not all alike; rather, they fall on a continuum with fully separated R&D sections at one end and fully integrated R&D sections at the other.
Within this continuum, three patterns emerge: blocked R&D, iterative R&D,
and integrated R&D.
In the blocked R&D pattern, a single block of results is followed by a single
block of discussion. For example, for a set of three results, the pattern would
be [results 1, results 2, results 3] [discussion 1, discussion 2, discussion 3]. In
essence, the blocked R&D pattern is identical to that of fully separate sections but
merged under a single “Results and Discussion” heading. In such papers, it is usually quite easy to determine where the Results section ends and the Discussion
section begins.
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The Journal Article
Blocked R&D
An approach for combined R&D sections in which all results are presented first, followed
by paragraphs dedicated to the discussion. For three sets of results, the pattern would be
as follows:
[R1, R2, R3] [D1, D2, D3]
In the iterative R&D pattern (the most common pattern), authors alternate
between presenting and discussing results. Thus, for three results, an iterative R&D
pattern is achieved as follows: [results 1, discussion 1] [results 2, discussion 2] [results
3, discussion 3]. The story of scientific discovery is often easier to tell (and understand) if each finding is presented and discussed before moving on to the next.
Iterative R&D
An approach for combined R&D sections in which authors alternate back and forth
between results and discussion. For three sets of results, the pattern would be as follows:
[R1 D1] [R2 D2] [R3 D3]
With the integrated R&D pattern, results are presented and discussed
together, often in the same paragraph or even the same sentence. The text is organized in a way that best conveys the story of scientific discovery, with no obvious
delineation between results and discussion. This pattern is less common, but
when done well is quite effective.
Integrated R&D
An approach for combined R&D sections in which results and discussion are seamlessly
integrated with no obvious pattern.
These patterns are intended to serve as guiding constructs only. In practice,
most authors who use combined R&D sections will combine features of two or
three patterns in their writing, making it difficult to find a pure example. For
example, in some articles, the R&D section may generally follow the blocked
R&D pattern, but authors may add some brief interpretative comments into their
presentation of results. Some journals specify a required format for the R&D section; hence, it is always a good idea to refer to the “Information for Authors” section of a journal before beginning to write a manuscript for publication.
Writing the Results Section
113
Despite the frequency with which combined R&D sections now appear in the
chemical literature, we have chosen to address the sections separately in this textbook. The different purposes of Results and Discussion sections are important to
understand and distinguish, even if you ultimately choose to write a combined
R&D section. In this chapter, we focus on the Results section. The Discussion
section and the integrated R&D approach are examined in chapter 5.
Reading and Analyzing Writing
In Results and Discussion sections, the reader should be led step-bystep through the subject, showing how conclusions unfold logically as the
results accumulate.
—Charles H. DePuy, University of Colorado–Boulder
We formally begin this chapter by asking you to read and analyze a Results section on your own. Excerpt 4A is a continuation of excerpt 3A (in chapter 3),
regarding the analysis of aldehydes in aged beer. The excerpt includes most of
the original text, but, to conserve space, only one figure (Figure 3) and one table
(Table 2) are included. Note that the excerpt is a combined R&D section.
Exercise 4.1
As you browse through excerpt 4A, consider the following questions:
a. Which organizational features and writing conventions (e.g., capitalization in abbreviations and subheadings, numerical formatting, and use of
parentheses) appear to be similar to those used in the Methods section?
b. What formatting conventions do you notice in the figure and table?
c. Which sentences or paragraphs belong in the Results section? Which belong
in the Discussion section? How does the language help you differentiate
between the two?
d. What did the authors do to make their writing concise?
Excerpt 4A (adapted from Vesely et al., 2003)
Results and Discussion
Identification. Identification of the carbonyl PFBOA derivatives was performed by
mass spectrometry using electron impact ionization running in the scan mode. It was
confirmed that fragment m/z 181 was the main fragment of all analyzed aldehydes (6).
Figure 1 shows as an example the mass spectrum of the PFBOA derivative of methional. To increase the selectivity of the method, all aldehyde analyses were run in the
114
The Journal Article
single-ion monitoring (SIM) mode with monitoring for m/z 181. Beer was also analyzed
by GC/MS without being derivatized by PFBOA in order to ensure that there were no
other sources of m/z 181 besides the derivatization agent.
Optimization of Derivatization Procedure. Three parameters that may affect the partition of aldehydes between the headspace and the solution were tested: derivatization time,
temperature, and ionic strength. The effect of pH was not examined because it was previously shown that the natural pH of beer, 4.5, is sufficiently low for the derivatization reaction (6). Therefore, the pH of standard mixtures was adjusted to 4.5 using 0.1% phosphoric
acid. Because methional appeared to be the most problematic aldehyde to detect, optimization was carried out in a 5% ethanol (pH 4.5) solution spiked with 5 ppb of methional.
The effect of temperature on the extraction of methional from ethanol solution and
its derivatization on a PFBOA-loaded fiber was examined for 35 and 50 ºC (Figure 2).
Increasing the extraction temperature caused an increase in the peak area of the derivatized methional. Based on this result, subsequent derivatizations were conducted at 50 ºC.
The optimal derivatization time was also tested. The ethanol solution spiked with
5 ppb of methional was exposed for 15, 30, 60, 90, and 120 min at 50 ºC. It was determined that the time to reach equilibrium between stationary phase and sample headspace was 90 min (Figure 3). A derivatization time of 60 min at 50 ºC appeared to be a
good compromise between the time of reaction and analyte response.
Relative abundance
120000
100000
80000
60000
40000
20000
0
50
30
60
90
120
Time (min)
Figure 3. Derivatization time versus detector response of PFBOA
derivative of methional.
Figure 4 shows that addition of salt (2 g of NaCl in 10 mL of methional solution) did
not have any effect on the extraction and derivatization procedure (60 min, 50 ºC).
Calibration. Most aldehydes, except formaldehyde, form two geometrical isomers
of the derivatives and appear as two peaks in the chromatogram. The sum of these two
peak areas was used in the calibration measurements. A six-point calibration curve
for nine carbonyl compounds was measured. The calibration range was 0.1–50 ppb,
except for (E)-2-nonenal, where the calibration range was 0.01–5 ppb. The matrix used
for calibration solutions was 5% ethanol solution, pH 4.5. Correlation coefficient (R 2)
values indicate that this method can be used for analysis of aldehydes in a wide range of
concentrations (Table 1).
Writing the Results Section
115
Method Validation. Reproducibility of the method was determined by analyzing one
beer sample 10 times. Table 1 shows that the method provides very good reproducibility,
with coefficients of variations for monitored aldehydes below 5.5%, except for (E)-2nonenal. The higher coefficient of variation for (E)-2-nonenal may be due to extremely
low levels of this aldehyde in the analyzed beer.
Beer Analysis. Nine aldehydes were detected in analyzed beer (Figure 5). The resolution
of two peaks, representing two geometrical isomers of each aldehyde, was good, except for
furfural, where the first peak was clustered with a peak of an uncharacterized compound.
The aldehydes 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, methional, and
phenylacetaldehyde are so-called Strecker aldehydes, formed as a result of a reaction
between dicarbonyl products of the Amadori pathway and amino acids, having one
less carbon atom than the amino acid (1). According to Schieberle and Komarek (8), the
increase of Strecker aldehydes and some esters might play a central role in fl avor changes
during beer aging. The same authors exclude (E)-2-nonenal, a degradation product of
linoleic acid, as a key contributor to the stale flavor of beer. Other aldehydes related to
the autoxidation of linoleic acid are pentanal and hexanal (1). Furfural, a product of the
Maillard reaction, is a known heat exposure indicator that does not impact beer fl avor
due to its high flavor threshold (9).
During long-term storage at elevated temperatures, American-style beers develop
a stale flavor (10). Analyzed beer samples were stored at 30 ºC for 4, 8, and 12 weeks.
Levels of all aldehydes increased during beer storage compared to the control sample
(Table 2). Although the increase after 12 weeks at 30 ºC was significant (16-fold increase
for furfural, 7-fold increase for 2-methylpropanal), none of the analyzed aldehydes
exceeded their fl avor threshold in beer (11). However, it is probable that additive or synergistic effects take place when aldehydes contribute to the stale flavor of aged beer.
Table 2. Aldehyde Level Changes (ppb) in Beer during 12 Weeks Storage at 0 and 30 °C
0 °C
12
4
8
12 weeks
2-methylpropanal
6.1
20
30.6
42.4
1000
2-methylbutanal
1.8
3.1
4.2
5.2
1250
3-methylbutanal
12.2
17.2
20.7
24.4
600
pentanal
0.3
0.6
0.7
0.8
500
hexanal
1.0
1.8
20.1
2.5
350
furfural
28.8
202.8
362
458.3
150000
methional
2.8
3.6
4.1
4.6
250
phenylacetaldehyde
6.6
9.9
10.1
12.7
1600
(E)-2-nonenal
0.01
0.02
0.02
0.03
a
116
FTa
30 °C
0.11
Flavor threshold in American-style beer (11).
The Journal Article
Because and Since
See appendix A for more information on these commonly confused words.
Exercise 4.2
Because excerpt 4A uses a combined R&D section, you likely found sentences that
are clearly results and sentences that are clearly discussion (see exercise 4.1c). Given
this observation, which combined R&D pattern do you think best characterizes this
excerpt: blocked, iterative, or integrated? Of course, the match may not be perfect.
Exercise 4.3
Compare this figure to Figure 3 in excerpt 4A. Using Figure 3 as a guide, identify
five formatting mistakes in the bar graph below (we found seven). (See chapter 16
for more information on formatting bar graphs.)
Figure 2.
14000
12000
10000
8000
Series 1
6000
4000
2000
0
15
min
30
min
60
min
90 120
min min
140
min
Exercise 4.4
Compare this table (adapted from Vesely et al., 2003) with Table 2 in excerpt 4A.
Using Table 2 as a guide, identify five formatting mistakes in the table below (we
found six). (See chapter 16 for more information on formatting tables.)
Table 1. Correlation Coefficient (R 2), Coefficient of Variations (CV),
and Relative Recovery (RR) of Analyzed Aldehydes
R2
CV
RR
2-Methylpropanal
.9639
4.7%
110%
2-Methylbutanal
.9723
4.6%
104%
3-Methylbutanal
.9706
4.0%
109%
continued
Writing the Results Section
117
Table 1 (continued)
R2
CV
RR
Pentanal
.9951
3.9%
114%
Hexanal
.9925
4.3%
103%
Furfural
.9892
5.1%
99%
Methional
.9983
2.4%
90%
Phenylacetaldehyde
.9839
5.3%
98%
(E)-2-Nonenal
.9944
8.0%
89%
Analyzing Audience and Purpose
An author’s central obligation is to present an accurate account of the
research performed as well as an objective discussion of its significance.
—American Chemical Society, Ethical Guidelines to Publication in
Chemical Research (https://paragon.acs.org/)
The central purpose of the Results section is to describe your research findings to
other scientists (an expert audience) in a clear and concise manner. As you will
see in chapter 5, the central purpose of the Discussion section is to interpret those
findings. The distinction between description and interpretation is not always
clear-cut. The following rule of thumb helps to distinguish between the two:
Description (Results) answers the question What did you find?
Interpretation (Discussion) answers the question What do your findings mean?
Truth?
Words such as truth and prove seldom appear in scientific writing. In a computer-based
analysis of 180 journal articles, prove was found only twice, and truth never occurred.
Hedging words are used instead. For example, data suggest (not prove), results offer
evidence (not proof), and findings (not truths) are reported.
Hedging is discussed in more detail in chapter 5.
An objective description of results allows readers to examine the data unbiased by interpretation. Results are sometimes viewed as a glimpse at the “truth”;
alternatively, interpretations are educated opinions that are likely to change over
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The Journal Article
time. As a writer, you must learn to distinguish between description and interpretation, especially if you write a combined R&D section. The following sentences
from excerpt 4A (referring to Figure 3) help to clarify the difference:
Description
The ethanol solution spiked with 5 ppb of methional was
exposed for 15, 30, 60, 90, and 120 min at 50 °C (Figure 3).
Interpretation The higher coefficient of variation for (E)-2-nonenal may
be due to extremely low levels of this aldehyde in the
analyzed beer.
That the spiked ethanol solution was exposed for different lengths of time at 50 °C
(presumably) conveys a “truth” or “fact” that will not change; thus, the statement
is descriptive. However, the higher coefficient of variation for (E)-2-nonenal may
not necessarily be due to the low levels of aldehydes in the analyzed beer; hence,
the statement is interpretive.
Exercise 4.5
The following statements are taken from the R&D section of an article that
reports on a study of tartary buckwheat as a source of dietary rutin (adapted from
Fabjan et al., 2003). For each sentence, decide whether its primary purpose is to
describe, interpret, or both:
a. The highest content of rutin, 2.5–3% dry weight, was observed as sampling
started.
b. Trends in rutin content were rather similar in all of the buckwheat varieties,
indicating a more important influence of environment than genotype on the
rutin content of the buckwheat herb.
c. Later sowing had essentially no impact on rutin content in herb, as shown in
Figure 2.
d. On the basis of this study, it is clear that buckwheat herb production is
feasible and that it could readily be produced as a nutritionally rich food, a
rutin-rich herb tea, or food additive.
4A Writing on Your Own: Read the Literature and Review Your Results
Read the Results sections of the journal articles that you collected during your literature
search (starting with Writing on Your Own task 2C). As you read these articles, pay attention
to how the authors organized their results and what results they chose to emphasize in
both text and graphics. What ideas do these articles give you about ways to write your
own Results section?
Now is also a good time to review your results. What have you learned from your data?
What do you want your readers to learn? You will not be able to share all of your results
Writing the Results Section
119
with your readers, so begin to think about the most important points that you want to
communicate.
Analyzing Organization
The purpose of the Results section is to present—without interpretation—the
results of the study. Two moves are suggested to accomplish this task (figure 4.1).
The first move, Set the Stage, serves to transition the reader from the Methods
to the Results section. Two submoves are involved: in submove 1.1, the reader
is briefly reminded how a particular set of results was obtained; in submove
1.2, the reader is referred to a graphic (a table or figure) that displays those
results. These complementary submoves are often accomplished in a single
sentence (a poignant reminder of the conciseness in chemistry writing). After
the graphic has been introduced, the authors shift to the second move, Tell the
Story of Scientific Discovery, where important findings are identified, trends are
highlighted, and unexpected results are underscored. Importantly, the story is
rarely told in the way that it actually occurred (chronologically); rather, it is told
in a way that logically leads the reader to the conclusions of the paper. These
two moves are repeated, as needed, for each set of results. Because these moves
describe quite specific information, the Results section is in the narrowest part
of the hourglass.
1. Set the Stage
1.1. Remind readers (briefly) how you obtained a set of results
1.2. Refer readers to a graphic that displays that set of results
2. Tell the Story of Scientific Discovery
Guide readers through the set results as you do
one or more of the following:
Identify key
findings and
discoveries
Describe
important
trends
Highlight
unexpected
results
Repeat (as needed) for each set of results
Figure 4.1 A visual representation of the move structure for a typical Results section.
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The Journal Article
Sets of Results
Results sections often include multiple sets of results. Each set presents a different piece
of evidence or a different part of the project. The various sets are linked to lead logically to
the conclusions of the paper.
Exercise 4.6
The authors of excerpt 4A present several sets of results using both text and
graphics (only two graphics are included here). These results include the optimization of temperature, time, and ionic strength. Reread excerpt 4A and consider
the third and fourth paragraphs, which present temperature and time results,
respectively. For each paragraph, determine how well the authors adhere to the
move structure in figure 4.1. Explain.
Exercise 4.7
Browse through three articles in one of the following journals: The Journal of
Organic Chemistry, Analytical Chemistry, Environmental Science & Technology, or
Chemical Research in Toxicology. How well do the articles adhere to the move structure illustrated in figure 4.1?
4B Writing on Your Own: Organize Your Results
Organize your data into one or more sets of results. (Omit results that led to false starts
or dead ends or that were preliminary in nature.) What evidence does each set of results
reveal? Organize the sets of results in a logical sequence so that the pieces of evidence
lead ultimately to the conclusion(s) of your work. (Remember that you do not need to
follow the actual order in which the data were collected.)
Analyzing Excerpts
Because we do not work in a vacuum in the academic world, we must
learn to communicate with others. The written word remains the
foundation of this communication, and I would hope that some of the
capstones in my career have come from being able to communicate in a
clear and controlled manner.
—Richard Malkin, University of California–Berkeley
Writing the Results Section
121
We are now ready to read and analyze excerpts of Results sections in more depth,
one move at a time. After examining the individual moves in part 1, we look
holistically at the Results section in part 2.
Part 1: Analyzing Writing Move by Move
Move 1: Set the Stage
The goal of move 1 is to transition the reader from the Methods section to the
Results section. The move begins with a brief reminder of how a set of results
was obtained and then refers the reader to a graphic that displays these results.
Consider the following passage:
P1 The EPR spectra of samples of PM2.5 from five different sites in the U.S.
are shown in traces A-E of Figure 1. (From Dellinger et al., 2001)
In one sentence, the authors remind us that PM2.5 was collected in five sites and
analyzed with EPR, and they refer us to Figure 1, which displays the EPR spectra.
(Details about PM2.5 and EPR were included in the Methods section.)
Referring to Graphics
Remember to refer to graphics before actually guiding readers through the results in
the text.
Avoid “dangling graphics,” that is, graphics that are included in a paper but never
mentioned in the text.
Note that the reference to the graphic (move 1) comes before guiding the reader
through the graphic (move 2). In this way, the reader has the opportunity to view
the data before reading the associated prose. Often, the graphic is introduced in
parentheses, as shown in the next two examples. Note, too, the use of subheadings in these passages; subheadings are a particularly effective way to direct the
reader’s attention to each set of results.
P2 Chromium Accumulation in E. coli Cells. The cellular uptake of
chromium is presented as milligrams of chromium per dry weight of
treated E. coli cells (Table 1). (From Plaper et al., 2002)
P3 Experiment 1. When fed at a concentration of 3 μg of Se/g of diet,
high-Se broccoli significantly reduced the incidence and total number
of mammary tumors as compared to rats fed 0.1 μg of Se/g of diet as
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either selenite alone or 0.1 μg of Se/g of diet in combination with low-Se
broccoli (Table 1). (From Finley et al., 2001)
Another common way to refer to a graphic in the text is with the phrase “as
shown in Figure__” or “are shown in Figure___.” Consider the following
example:
P4 The first part of this study involved structurally differentiating between
hazelnut oil and other oils and then detecting adulterating oils in
hazelnut oil. For this purpose, the spectra of pure hazelnut oil were
compared with the spectra of seven other oil types, as shown in Figure 1.
(Adapted from Ozen and Mauer, 2002)
“As shown in Figure __”
What’s the most common four-word combination in a chemistry journal article?
“as shown in Figure”
(based on a computer-based analysis of 200 journal articles)
Exercise 4.8
How well do passages P1–P4 set the stage (move 1)? For each passage, predict
what the results will be about, even though you have not read the Introduction
or Methods section.
Exercise 4.9
Both past tense and present tense are used in passages P1–P4. Find instances of
both and explain when each is used. Based on your answer, select the right tense
for this sentence: The data are/were shown in Table 1.
Exercise 4.10
Based on passages P1–P4, describe how the words “table” and “figure” should
be formatted in the text. Identify three ways in which you can refer to a table or
figure in the body of your text.
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123
Move 2: Tell the Story of Scientific Discovery
After the stage is set, you are ready to tell the story behind the data. The story
is told using both text and graphics (typically tables and figures). Most authors
determine the order of their graphics first (Table 1, Figure 1, Figure 2, Table 2,
etc.), as well as the order of the data within each graphic (entry 1, entry 2, etc.),
and then write the prose to complement the graphics. Ultimately, the graphics
and prose should work together, reinforcing but not duplicating one another; the
reader’s attention should naturally be shifted back and forth between the two.
That said, we point out that graphics are not required in all instances, and occasionally an article will be published with no figures or tables. Indeed, graphics
should only be included if there is sufficient data (see chapter 16 for guidelines
on how much data is needed for tables and figures), and if the graphics make the
data more accessible to the readers. Graphics that are superfluous or that repeat
content that is easily described in the text will detract from rather than enhance
the Results section.
The Bare Minimum
See chapter 16 for guidelines on how much data you need for a table or figure.
The best way to learn how to write a Results section is to read and analyze
Results sections from the literature. To this end, we examine excerpts (prose and
graphics) from six published Results sections. We guide you through the content of these articles, elucidate what the authors have “discovered,” and analyze
how the authors have organized their results. (In each case, the original articles
had multiple sets of results, but for brevity, we include only a few.) As you read
these excerpts, pay particular attention to how the authors use text, in combination with graphics, to describe their data (i.e., to identify important findings,
describe trends, and highlight unexpected results). In subsequent chapters, we
read additional excerpts from these articles, taken from the Discussion sections
(chapter 5), Introduction sections (chapter 6), and abstracts (chapter 7).
4C Writing on Your Own: Prepare Figures and/or Tables
Select the data that you plan to present in a figure or table. We recommend that you
include at least one figure or table in your paper. Check to be sure that you have enough
data for the graphic (if not, ask your instructor for possible sources of additional data).
Organize the information in the graphic in a logical sequence. You will follow this sequence
as you write the text that accompanies your graphic.
Create the figure and/or table using guidelines in this chapter and in chapter 16.
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We begin with an excerpt from Environmental Science & Technology (excerpt 4B).
In a combined R&D section, the authors tell us what happened when they coated
different types of soil with randomly methylated β-cyclodextrins (RAMEB).
Cyclodextrins are highly water-soluble, crystalline sugars; their shape (referred to
as toroidal) resembles a water pail without a bottom. The outer surfaces of the pail
are hydrophilic (water-loving), which accounts for their solubility in water and
their ability to attract water molecules. RAMEB alone adsorbs water molecules;
hence, the authors predicted that RAMEB-coated soils would adsorb more water
than their noncoated counterparts.
To test this theory, the authors measured water vapor adsorption isotherms for
RAMEB-treated soils. The amount of water adsorbed (kg water/kg soil) was monitored as a function of the partial pressure of water (p/po), the dose of RAMEB in
the soil (0, 1, or 9%), and the type of soil. Seven soils were studied and arranged
in order of increasing clay content (3, 8, 11, 16, 25, 36, and 49% clay content for
S1, S2, S3, . . . S7, respectively).
With that background, let’s look at excerpt 4B. The authors use subheadings to
present each set of results (only the first set of results is included in excerpt 4B).
The opening sentence (in accord with move 1) reminds us how this set of results
was obtained and refers us to Figure 1. Recall that seven soils were studied, but
only three are plotted in Figure 1 (a low-, medium-, and high-clay-content soil).
The authors realized that the trends in their data would be clearer if they graphed
representative data only, not all of the data. Novice writers might have been
tempted to include three figures, one for low-, one for medium-, and one for highclay-content soils. Such an approach, however, would have made the trends more
difficult to discern.
Representative Data
Avoid the temptation to plot all of your data. Instead, plot only representative data, the
data needed to illustrate important trends in your study.
In the corresponding text, the authors emphasize the important trends: clay-rich
soils show lower adsorption, clay-poor (sandy) soils show higher adsorption, and
soils with medium clay content show intermediate adsorption, when compared to
their untreated counterparts. Moreover, the unexpected behavior of the clay-rich
soils is highlighted. The authors first state the expected behavior (“An increase in
water sorption was expected after RAMEB addition to all soils.”) and then point
out the unexpected behavior (“However, the isotherms for RAMEB-treated clayrich S6 and S7 soils show lower adsorption than the original soils.”). Because this
is a combined R&D section, the authors also offer a tentative interpretation for
the unexpected finding (“that RAMEB decreases the amount of water-available
surfaces in clay-rich soils”).
Writing the Results Section
125
Exercise 4.11
Read and analyze excerpt 4B (text and figure) to determine what the adsorption
isotherm measurements reveal and then answer the following questions:
a. How quickly do the authors refer to Figure 1?
b. What trends revealed in the graph do the authors describe in the text? Are
there any unexpected findings? If so, how are they highlighted?
c. Explain why the authors included only three of the seven soils studied
(S2, S5, S7) in Figure 1.
d. Excerpt 4B is an example of an iterative R&D section. In the full journal
article, the authors report numerous sets of results; for brevity, only the first
set of results is included here. In excerpt 4B, how do the authors present their
results regarding sandy soil? How are these results discussed?
e. Examine the symbols the authors used to graph the data. What pattern
guided their approach? Comment on the advantages and disadvantages of the
approach that they selected. (See chapter 16 for recommendations for symbol
selection.)
Excerpt 4B (adapted from Jozefaciuk et al., 2003)
Results and Discussion
Effect of RAMEB on Water Vapor Adsorption on Soils. Experimental adsorption
isotherms for the RAMEB-treated soils are presented in Figure 1 [see p. 127]. As pure
RAMEB sorbs a very high amount of water (ca. 1 g g–1 at p/p0 = 0.99), an increase in
water sorption was expected after RAMEB addition to all soils. However, the isotherms
for RAMEB-treated clay-rich S6 and S7 soils showed lower adsorption than the original soils, which is illustrated for S7 soil with 49% clay. This potentially indicates that
RAMEB decreases the amount of water-available surfaces in clay-rich soils, similar to
what was observed for pure clay minerals (20). In sandy soils (S1–S4), the water sorption
markedly increased, particularly at higher RAMEB doses, as is illustrated for S2 soil.
This may be attributed to water sorption by free RAMEB, that is, RAMEB molecules that
did not interact with the sandy soils. For soil S5 of medium clay content (25%), the effect
of RAMEB on water sorption was small, which can reflect a balance between the two
tendencies described above.
Excerpt 4C is taken from an article in Analytical Chemistry. Headspace solidphase microextraction (HSSPME) is coupled with GC to quantify polychlorinated
biphenyls (PCBs) in milk. The PCBs are volatilized out of the liquid phase (milk)
into the gas phase (headspace) and concentrated on an SPME fiber. The concentrated PCBs on the fiber are then injected into the GC.
This excerpt offers an excellent example of what we mean by the “story of
scientific discovery.” The authors guide us through their discovery process,
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adsorption, kg kg–1
S2(0)
S2(1)
S2(9)
S5(0)
S5(1)
S5(9)
S7(0)
S7(1)
S7(9)
0.04
0.03
0.02
0.01
0
0
0.2
0.4
0.6
p/po
Figure 1. Water vapor adsorption isotherms for
RAMEB-treated soils. Soil symbols are as in Table
1. The number in parentheses following the soil
symbol is the dose of RAMEB (%).
highlighting first the successful analysis of PCBs in skim milk, then the unsuccessful analysis of PCBs in full-fat milk, and ultimately, the successful analysis
of PCBs in full-fat milk. The story appears to follow chronological order, but this
need not be the case. What’s important is that the authors purposefully sequenced
their results to make the story easy to follow. Their logical presentation makes it
clear that the problem involves full-fat milk, and this problem can be solved with
saponification.
Scientific Terms (excerpt 4C)
HSSPME
Headspace solid-phase microextraction; a preconcentration technique
that concentrates volatile analytes on a fiber than can be inserted
directly into a GC
ECD
Electron-capture detector; a detector that is very sensitive to
halogenated compounds
Saponification The process of converting a fat (RCOOR′) to its corresponding
carboxylate anion (RCOO¯) and alcohol (R′OH) by reaction with NaOH
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127
Chronological Order?
Results may appear to be presented in chronological order, but usually they are not. Actual
chronological order is often quite messy because of false starts, dead ends, and “wrong
turns.” True chronological order only confuses the reader.
Instead, effective writers use hindsight to intentionally rearrange their results in a logical
sequence of events.
Exercise 4.12
As you read excerpt 4C, examine the figure and text carefully to determine what
the HSSMPE-GC measurements revealed. Answer the following questions:
a. What sentences accomplish the goals of move 1?
b. List the sequence of events portrayed by the authors in graphics and text to
tell their story of scientific discovery.
c. The figure contains a lot of information. Was all of the information described
in the text? What aspects of the graphic were most important to the authors?
d. The authors use a combined R&D section. Find examples of both description
and interpretation.
e. Comment on why you think that the authors included panel B in Figure 1 of
their article instead of simply reporting a more concise story (e.g., “Method A
works for skim milk” and “Method B works for full-fat milk”).
Excerpt 4C (adapted from Llompart et al., 2001)
Results and Discussion
Preliminary Experiments. Influence of Fat Contents. Initial HSSPME experiments
were performed using spiked skimmed and full-fat milk samples. . . . Figure 1A shows
the ECD chromatogram obtained for the skim milk. When the same experiments were
performed on full-fat milk, the results were considerably lower, as can be seen in the
chromatogram shown in Figure 1B. Also, in the full-fat milk sample, the background
appeared higher, and it increased after each SPME injection. This indicates that this
simple procedure might be adequate for the analysis of PCBs in milk samples having low
fat content; however, it is not adequate when the percentage of fat increases. This is quite
logical because PCBs are more strongly retained in the sample matrix as the fat content
increases. . . .
Taking into account these results, our objective was to develop a SPME procedure
that improved the release of PCBs from the sample to the fiber coating irrespective
of the fat content of the samples. Saponification of fats to their corresponding glycerols and carboxylates facilitates the release of PCBs from fatty matrixes and also can
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8
5
counts
25000
1
7
20000
(A)
9
6
4
15000
3
10000
2
5000
0
0
5
10
15
20
25
30
35
40 min
counts
25000
20000
(B)
15000
10000
1
5000
2
3
4 56 7
20
25
8 9
0
0
5
10
15
30
35
40 min
counts
25000
20000
(C)
15000
1
10000
3
2
5000
0
5
10
15
20
4
5 7
6
8
25
30
9
35
40 min
Figure 1. HSSPME-GC-ECD chromatograms of spiked milk samples: (A) skim milk;
(B) full-fat milk; (C) full-fat milk after saponification. Peak identification: (1) PCB-28,
(2) PCB-52, (3) PCB-101, (4) PCB-118, (5) PCB-105, (6) PCB-153, (7) PCB-138, (8) PCB156, and (9) PCB-180.
selectively degrade many other interfering substances without affecting the PCBs.1 Sets
of preliminary HSSPME experiments were run after 2 mL of 20% NaOH was added to
the samples. Figure 1C shows the chromatogram obtained by HSSPME for the full-fat
milk with the addition of NaOH solution. When comparing chromatograms B and C in
Figure 1, we can see the increase in response, as well as the lower background obtained,
after saponification.
Excerpt 4D is from Chemical Research in Toxicology. The authors investigate the
genotoxicity of three different chromium (III) compounds (chromium chloride,
Writing the Results Section
129
chromium nitrate, and chromium oxalate) and link several sets of results (we
consider only three) to make their case. As we will see, the organization of these
results is important for convincing the readers of their conclusions.
The first set of results (not included in excerpt 4D) presents data from a ProTox (C) assay, a test that looks at 13 possible stress promoters that can be induced
in bacteria by the chromium compound(s) under investigation. According to this
test, both chromium chloride and chromium nitrate induced similar stress promoters, producing profiles indicative of DNA damage. Alternatively, chromium
oxalate induced very few stress promoters, and its profile was not indicative of
DNA damage. As the authors state (italics added): Interestingly, none of the 13 stress
promoters were induced when bacteria were treated with chromium oxalate (Figure 2).
The authors use the word interestingly to call the reader’s attention to the observation that chromium oxalate is somehow different than chromium chloride and
chromium nitrate. As you will see, this statement foreshadows results that are
presented in excerpt 4D.
Interestingly, . . .
Authors sometimes use the word interestingly to foreshadow a result that will be explained
in more detail elsewhere in the paper. The word is most effective when used only once in
a paper.
Presumably, for DNA damage to occur, chromium must enter the cell. The
second set of results (excerpt 4D) addresses this issue. The authors look for chromium uptake inside E. coli cells using a technique known as flame atomic absorption spectroscopy (FAAS). These results build on the authors’ first set of results,
providing additional evidence that chromium oxalate is somehow different than
the other chromium compounds studied.
Exercise 4.13
Read and analyze excerpt 4D to understand what the table and text reveal. Then
answer the following questions:
a. What data in the table do the authors choose to emphasize in the text?
b. How does the information presented in excerpt 4D build on the results of the
Pro-Tox (C) assay (see description of full article above)? What new insights
do you have into the genotoxicity of Cr3+?
c. How well do the authors adhere to table-formatting conventions (see
chapter 16)?
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Scientific Terms (excerpt 4D)
E. coli Escherichia coli, bacteria that live in the human intestinal tract. Some strains of E.
coli are harmless; others cause diarrhea-like symptoms. The Pro-Tox (C) assay and
the Cr3+ tests use E. coli K-12 strains. (Note that the genus and species names are
italicized and the E. is capitalized. See chapter 3.)
FAAS Flame atomic absorption spectroscopy; the flame atomizes metals in solutions.
Once in the gas phase, the atoms absorb UV–vis light, exciting electrons to
higher energy levels. The amount of light absorbed is used to determine the
metal concentration.
Excerpt 4D (from Plaper et al., 2002)
Chromium Accumulation in E. coli Cells. The cellular uptake of chromium is
presented as milligrams of chromium per dry weight of treated E. coli cells (Table 1).
FAAS measurements of total chromium concentrations in E. coli cells showed that only
chromium chloride and chromium nitrate accumulate intracellularly but not chromium
oxalate. As shown in Table 1, at all concentrations of chromium oxalate used, the quantity of chromium was below the detection limit.
Table 1. Uptake of Chromium by E. coli Cells Treated with Different Cr3+ Compounds
Cr3+ compound
concentration of added
compound (mM)
intracellular content of Cr
(mg of Cr/g of dry weight)
CrCl3 × 6H 2O
0
0.63
1.25
<0.021
1.8
6.7
Cr(NO3)3 × 9H 2O
0
0.63
1.25
<0.021
2.4
5.7
KCr(C2O4)2 × 3H 2O
0
0.63
1.25
<0.025
<0.022
<0.02
In the third set of results (not included in excerpt 4D), the authors examine how Cr3+ affects gyrase, an enzyme that regulates the ability of supercoiled
DNA to relax. Results, however, are reported only for chromium chloride, not for
chromium oxalate or chromium nitrate. By omitting these latter two compounds,
the authors illustrate what we call a broad-to-narrow approach. At the start of a
research project, there are typically many variables; however, as knowledge is
gained, some of these variables can be eliminated. In this case, chromium oxalate
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131
was eliminated because it does not enter the cell; chromium nitrate was eliminated because it mimics chromium chloride. Even if the authors had conducted
the third test on all three compounds, the Results section is best written without
this information. Authors risk diluting relevant results by including extraneous
data that fail to advance their story. We will see the broad-to-narrow approach
again in excerpt 4E.
Broad-to-Narrow Approach
Chemists often limit the number of variables in later experiments, based on information
acquired in earlier work.
This approach also applies to writing. Authors begin by sharing results for many variables, then limit their focus to only those that advance their story.
Before moving on to excerpt 4E, we call your attention to two ways in which
the concept of zero is addressed in excerpt 4D. First, we consider the concept
of zero in measured concentrations (i.e., the concentrations reported in the last
column of Table 1). Recall that no chromium oxalate was detected in the cells;
however, the authors do not report this with a zero. Rather, they use the phrase
“below the detection limit” in the text and the less-than symbol (e.g., <0.025
mg/g) in Table 1, which puts an upper limit on the amount of chromium oxalate
present. Novice writers might (incorrectly) suggest that “no chromium was present” in the text and use a zero in the table (0 mg/g). Such uses of zero, however,
are incorrect, because (for measured concentrations) zero varies with the sensitivity of the detecting instrument. For example, on one instrument, zero will be less
than one part per million; on a more sensitive instrument, zero will be less than
one part per billion. Instead of reporting zero, authors report that the measurement was below the detection limit for that instrument. Some common ways to
express this concept in the text and table are as follows:
In the text X was not detected
X could not be detected
We did not detect X
X was below detection limits
In a table
<0.02
bdl (below detection limits)
ND (not detected)
Alternatively, it is correct to use zero to indicate added amounts of compounds. You
may say “that no chromium oxalate was added” and use a “0” to indicate this in a
table. For example, the second column of Table 1 includes three zeroes, indicating
that no chromium compounds were added to the cells in these three experiments.
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Zero?
Measured concentrations should not be reported as zero, even if the substance is not
detected. A more sensitive instrument (one with a lower detection limit) might be able to
detect it. In other words, even if you don’t “see” the substance, it might be there!
Excerpt 4E is taken from an article in Chemical Research in Toxicology and
involves the toxicity of fine particulate matter, airborne particles with effective
diameters ≤2.5 µm (also known as PM 2.5). The fine particulate was collected using
a PM2.5 monitor. Ambient air is pulled through the monitor, diverting the larger
particles (≥2.5 µm) and capturing only the smaller ones onto a filter. Such fine
particles arise from a number of sources including industrial emissions, vehicle exhaust, and forest fires and may lead to asthma, bronchitis, and possibly
cancer.
Like excerpt 4D, the authors of excerpt 4E present multiple sets of results and
use a broad-to-narrow approach. In the first set of results (not shown), the authors
display electron paramagnetic resonance (EPR) spectra of PM2.5 collected at five
U.S. cities. The EPR data indicate that free radical concentrations in the PM 2.5
samples are high and at times exceed the free radical concentrations in cigarette
smoke. In the second set of results (not shown), the authors present results from
a comet assay, an electrophoresis technique. Cells without DNA damage migrate
together as a group, forming what looks like a comet’s head; cells with DNA damage migrate faster and at different rates, forming what looks like a comet’s tail.
The tail moment, a measurement of the tail length, is used to assess the amount
of DNA damage. Two types of human cells (K562 myeloid leukemia cells and
IB3–1 lung epithelial cells) were treated with extracts from the PM2.5 filters and
from “blank” (clean) filters. Cells treated with PM2.5 extracts showed significantly
greater tail moments and more DNA damage (74–90%) than cells treated with
blank extracts (0–14%).
Thus far, the results have highlighted two findings: (1) PM2.5 contains free
radicals and (2) PM2.5 causes DNA damage. The next logical step is to link the free
radicals to the DNA damage. As yet, the authors have not done this. Perhaps other
toxins in the PM2.5, such as metals, are causing the DNA damage. Can the authors
strengthen the case for the free radicals?
To this end, the authors perform a second comet assay. Only limited results,
however, are shared; PM2.5 from only one city (Baton Rouge) was tested using
only one cell line (K562 myeloid leukemia cells), thereby following a broad-tonarrow approach. The results are presented in excerpt 4E. As shown in Figure 3
(excerpt 4E), cells were exposed to (A) a blank extract, (B) a PM2.5 extract, (C,
D, E) a PM2.5 extract mixed with one of three different free radical scavengers,
(F) a positive control, and (G, H) a PM2.5 extract mixed with one of two different metal-ion chelators. The free radical scavengers remove free radicals; the
Writing the Results Section
133
metal-ion chelators remove metal ions, thereby preventing them from causing
DNA damage. If damage occurs without the additive, but disappears or is reduced
with the additive, then the radical (or metal) is likely causing the DNA damage.
With this background in mind, complete exercise 4.14 as you read excerpt 4E.
Can you figure out what is causing the damage in the cell DNA? What is the conclusion of the authors’ story?
Scientific Terms (excerpt 4E)
Organic compounds to which metal ions (e.g., Fe3+) bind
(or chelate) to form a complex, where the metal ion is in
the center of a ring, coordinated to two or more organic
species
Electrophoresis
The movement of particles in a gel due to electrodes
(positive and negative) applied to opposite ends of
the gel
Free radical
A highly reactive species with an unpaired electron and
no charge (e.g., the hydroxyl radical, HO˙)
In vivo
In the living cell (written without italics)
In vitro
In glass, like a test tube (written without italics)
Positive or negative controls Substances that are known to give a positive or
negative result; controls are used to check that the
experimental design and instrumentation are working
correctly.
Chelators
Exercise 4.14
Use the following questions to unravel the authors’ story of scientific discovery
in excerpt 4E:
a. Explain why the authors treated the cells with a blank filter extract and
H2O2. What do these cell treatments tell us?
b. Using Figure 3 and Table 2 in excerpt 4E, decide which of the following is
(are) most likely causing DNA damage (there may be more than one correct
answer):
■
■
■
free radicals
Cu2+/Cu+
Fe3+/Cu2+
c. The authors use “0” in Table 2 to report the percentage of cells with DNA
damage. Explain why the use of “0” is correct in this instance. (Hint: “0” is
used in a relative way and is related to the percent damage observed in the
blank filter extracts.)
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d. Consider the order in which the authors reveal their results, beginning with
the EPR and comet assay tests described in text (before the excerpt), and
ending with the comet assay test on the K562 cells treated with the Baton
Rouge extract (Figure 3, in excerpt 4E).
1. List the order in which the authors reveal their results.
2. Offer a rationale for why the authors followed this order.
3. Do you think the order is chronological? Explain.
e. The authors of excerpts 4D and 4E begin their Results sections by reporting
findings that are quite broad in scope (i.e., the toxicity of Cr3+ from three
compounds and the toxicity of PM2.5 from five cities), but they end with
findings with a more narrow focus (i.e., Cr3+ from only CrCl3 and PM2.5 from
only Baton Rouge). Why do you think the authors shift from a broad to a
specific focus? How might this approach make the story of discovery easier
to follow?
Excerpt 4E (adapted from Dellinger et al., 2001)
Results
To understand the mechanistic basis for the DNA damage, additional in vitro and
in vivo experiments were undertaken that involved the use of free-radical scavengers
and metal chelators to determine what effect they may have on PM 2.5-mediated DNA
damage. Because of their greater sample masses and availability, these experiments were
performed using the 5-day samples collected from the Baton Rouge site.
These studies were performed in vivo using human myeloid leukemia K562 cells.
This cell line was chosen because it lacks p53-induced apoptosis that causes doublestrand breaks and whose presence could therefore complicate the interpretation of
our results (40). As shown in panel A of Figure 3 [see p. 136], extracts from a blank,
unloaded fi lter left 72% of the DNA from K562 cells undamaged, whereas extracts
from fi lters containing PM 2.5 left just 24% undamaged DNA (panel B). Superoxide
dismutase (SOD) (panel C), catalase (panel D), and catalase plus SOD (panel E) all
provided complete protection of the DNA. Exposure of the cells to 100 µM hydrogen
peroxide (panel F) was used as a positive control (35) and produced 100% damaged
DNA. As shown in panel H, the Fe 3+ and Cu 2+ chelator deferoxamine provided almost
complete protection, but the Cu2+/Cu+ chelator bathocuproine, as shown in panel G,
provided only partial protection.
The fitted means and standard errors for log-transformed comet tail moments, as well
as the percentage of cells exhibiting extensive DNA damage (e.g., cells labeled 3 and 4)
are reported in Table 2 [see p. 137]. An adjusted p value indicated no differences existed
between cells treated with extracts from exposed filters or with hydrogen peroxide.
Cellular responses were significantly different (P < 0.05) between unloaded PM 2.5 filter
extracts and loaded PM 2.5 extracts as well as extracts containing deferoxamine.
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Figure 3. Comet assay is shown for human K562 cells
exposed to an extract produced from particulate matter
released from sample PM2.5 filters, to an extract derived
from an unloaded filter, or to hydrogen peroxide
(100 µM) as a control. Cells with little or no DNA
damage are labeled 1 and 2, and those with extensive
damage are labeled 3 and 4.
In the articles from which excerpts 4D and 4E were taken, reported results represent only a small fraction of the data actually collected. The authors found ways
to condense their data as they wrote their papers. In excerpt 4D, the authors condensed their data by reporting only representative results (i.e., results from three
soils instead of all seven). In excerpts 4D and 4E, the authors initially reported
multiple variables (i.e., three chromium compounds and five cities) but ended
with a narrower focus (i.e., one chromium compound and one city). In each case,
the readers benefited from the researchers’ hindsight. Learning to tell your story
of scientific discovery in retrospect, by reorganizing your data and highlighting
only the most illustrative pieces, is an essential skill in effective writing.
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Table 2. Results of Comet Assays for K562 Cells Treated with Baton Rouge
PM2.5 Extract
adjusted tail moment
(SE)
cells with DNA
damage (%)
blank filter extract (A)
PM 2.5 extract alone (B)
16.63 (0.19)
18.02 (0.20)
28
76
PM 2.5 extract plus free radical scavenger:
SOD (C)
catalase (D)
SOD & catalase (E)
positive control: H 2O2 (100 µm) (F)
15.25 (0.19)
13.60 (0.19)
15.36 (0.19)
18.03 (0.20)
0
0
0
100
PM 2.5 extract plus metal chelator:
bathocuproine (Cu2+/Cu+) (G)
deforoxamine (Fe3+/Cu2+) (H)
15.80 (0.78)
14.18 (0.14)
72
4
cell treatment (label in Figure 3)
The final two excerpts (excerpts 4F and 4G) illustrate a few ways in which
results from a chemical synthesis can be described. The Results sections of synthesis papers often include a hint of what was tried and failed as well as what
ultimately succeeded. Reading these excerpts will give you a feel for the trial-anderror process of science and the “aha” experience that sometimes occurs when a
successful approach is discovered.
Excerpt 4F is taken from an article written by Demko and Sharpless. (Barry
Sharpless was a co-recipient of the Nobel Prize in Chemistry in 2001 for his work
on chirally catalyzed oxidation reactions.) In this article, the authors propose a
way to synthesize aromatic tetrazoles from nitriles in water, using only sodium
azide and a zinc salt. Water, despite its obvious advantages (i.e., safe and inexpensive), rarely succeeds as a solvent in organic synthesis. Thus, a synthesis that uses
water successfully is an important scientific accomplishment.
We begin our analysis of excerpt 4F by examining its use of compound labels.
You have seen compound labels before. The ubiquitous R group (R, R′, R, . . . or
R1, R 2, R 3, . . . ) in organic chemistry, used to connote radical or residue (e.g., CH3 –
or CH3CH2– in R–Br), is one example. Another example is when authors include
a bolded number (or bolded number and letter) immediately after the name of a
compound in the text or table. Consider the following example, where 1 and 2
are the compound labels:
A mixture of 2-bromo-4-methoxyphenone 1 was reacted with
p-toluenesulfinic acid sodium hydrate 2.
After being introduced, 1 and 2 can be used instead of the compound names,
thereby saving considerable space. The numbers are bolded so that they can
be easily differentiated from other numbers in the sentence, such as citation
Writing the Results Section
137
numbers, which are never bolded. In some journals, the bolded number is placed
inside parentheses.
Compound Labels
Compound labels, in addition to being concise, focus attention on important features of
a reaction. They allow authors to communicate the versatility and generality of a reaction,
mechanism, or scheme efficiently. (See appendix A for more details.)
Let’s examine the use of compound labels in excerpt 4F. The authors first
use compound labels in their eq 1 (our eq 4.1) to illustrate the conversion of an
unspecified nitrile 1 to an unspecified tetrazole 2:
R
C
N
1.1 equiv NaN3
1.0 equiv ZnBr2
NH
R
water
reflux
1
N
N
N
(4.1)
2
In Table 2 of excerpt 4F, labels for specific tetrazoles (2a, 2b, 2c, . . . 2j) are introduced. Table 2 also provides the information needed to unlock the specific structures of 1 and 2 in the authors’ eq 1. For example, in table entry 2a, the R group
on the tetrazole is phenyl; hence, R is also phenyl on the nitrile, and their eq 1
becomes explicitly (our eq 4.2)
N
C
1a
N
1.1 equiv NaN3
1.0 equiv ZnBr2
water
reflux
N
NH
N
(4.2)
2a
Exercise 4.15
Glance ahead to excerpt 4F. Examine the connections between the compound
labels used in eq 1 and Table 2. Use these connections to complete eq 1 when 2c
is the product formed.
In journals such as The Journal of Organic Chemistry and Organic Letters, equations
are often included in tables, and the equation and table entries are linked by compound labels. Exercises 4.16 and 4.17 illustrate this convention.
138
The Journal Article
Exercise 4.16
Consider the following table, adapted from Usugi et al. (2004):
Table 1. GaCl3-Mediated Reaction of Various Alkynes with Disulfide a
R
H
+
RSSR
GaCl3
PhH
R
R'S
0 ˚C, 30 min
1
2
entry
R
1
1
n-Bu
1a
2
i-Pr
3
R′
SR
H
3
2
3
yield (%)
Ph
2a
3a
83
1b
Ph
2a
3b
58
t-Bu
1c
Ph
2a
3c
50
4
Ph
1d
Ph
2a
3d
87
5
Ph
1d
p-Tol
2b
3e
84
a
Disulfide (0.50 mmol), alkyne (0.75 mmol), GaCl 3 (0.50 mmol), and PhH (2 mL)
were employed.
The table includes an equation depicting a general chemical reaction (1 + 2 → 3).
The table entries describe five specific reactions by defining R and R′ in each case.
Using Table 1, write out the specific reactions for entries 2–5. Entry 1 has been
completed for you (R = n-Bu and R′ = Ph):
n-Bu
H
1
+
PhSSPh
2
GaCl3
PhH
n-Bu
SPh
0 ˚C, 30 min
PhS
H
3
Exercise 4.17
Imagine that you are in a research group that measures the relative rates of
nucleophilic substitution (SN2) reactions. The reactions that you have investigated are listed below. Prepare a table, like Table 1 in exercise 4.16, to summarize these reactions. Include the following equation at the top of the table:
R–Br + Nu– → R–Nu + Br –. Use compound labels to link the equation and table
entries.
Writing the Results Section
139
Reaction
Relative Rate
→ t-BuCl
+ Cl–
+ Br –
<1
neopentylBr + Cl
–
→ neopentylCl + Br
–
1
+ Cl
–
→ i-PrCl
+ Br
–
500
+ Cl
–
→ EtCl
+ Br
–
40,000
+ Cl
–
→ MeCl
+ Br
–
2,000,000
→ MeOOCH3 + Br
–
1,000,000
→ MeOH
+ Br
–
32,000,000
+ Br
–
200,000,000
t-BuBr
i-PrBr
EtBr
MeBr
MeBr
+ CH3COO
MeBr
–
+ HO
MeBr
+ I
–
→ MeI
–
Excerpt 4F does a good job of moving the reader’s attention back and forth
between the table and text, highlighting important results, but not repeating the
data. As you read the text and table together, it becomes clear that the authors
have organized their table not in an arbitrary way, but according to nitrile type
(aromatic, electron-poor aromatic, electron-rich aromatic, etc.). This organization
helps the reader see trends in the data.
Excerpt 4F (adapted from Demko and Sharpless, 2001)
[From Introduction section]
We report here a safer and exceptionally efficient process for transforming nitriles 1 into
tetrazoles 2 in water; the only other reagents are sodium azide and a zinc salt (eq 1).
R
C
1
N
1.1 equiv NaN3
1.0 equiv ZnBr2
N
NH
R
water
reflux
N
N
(1)
2
[From a combined R&D section, although no heading was included]
A wide variety of nitriles were converted to tetrazoles on a 20 mmol scale. Other things
being equal, the more electron-poor a nitrile, the faster it reacts. Aromatic nitriles (see
Table 2) with a variety of substituents (2a,b,c,i) reach completion within several days
at reflux. Electron-poor aromatic and heteroaromatic nitriles, such as 2-cyanopyridine
and cyanopyrazine (2d,e), are complete within a few hours. Some electron-rich aromatic
nitriles (2f,g) require higher temperatures, which are achieved using a sealed glass pressure reactor. Ortho-substituted aromatic nitriles are the most challenging, sometimes
proceeding at reflux (2h), but often requiring much higher temperatures (2j). We have
not been able to achieve significant conversion of any aromatic nitriles bearing an
sp3-hybridized substituent in the ortho position.18
140
The Journal Article
Table 2. Aromatic Tetrazoles
tetrazole a
entry
N NH
2a
N N
2b
O2N
2c
MeO
N NH
N N
N NH
N N
N NH
2d
N
N
N NH
2e
N
2f
HO
N N
N N
N NH
N N
temp/time
yield (%)
mp (°C)
reflux/24 h
76
215–216
reflux/24 h
94
220
reflux/48 h
86
231–232
reflux/6 h
79
211
reflux/2 h
83
193–195
140 °C/24 h
96
234–236
140 °C/48 h
73
205–207
reflux/48 h
64
228–230
reflux/12 h
67
158–160
170 °C/48 h
67
150
N NH
2g
N N
N N
NH
N
2h
N
NH
N N
NH
2i
O O
N NH
N N
OH
N NH
N N
2j
a
These reactions were run on 20 mmol scale.
Writing the Results Section
141
Excerpt 4G involves a variation of a bioorganic reaction known as the Strecker
synthesis. The Strecker synthesis is a two-step process that leads to the formation
of an α-amino acid, the building block of proteins. The general structure of an
α-amino acid involves a tetrahedral carbon (the α-carbon) bonded to an amino
group (–NH2), a carboxylic acid (–COOH), a hydrogen (–H), and a variable side
chain (–R). Of the 20 naturally occurring α-amino acids found in proteins, 19 are
chiral, all with a counterclockwise (S) configuration. This makes the (S) amino
acid a desirable synthetic target and motivates the asymmetric Strecker synthesis.
Unlike the Strecker reaction, which results in a racemic (50:50) mixture of the (S)
and (R) α-amino acid, the asymmetric Strecker reaction leads to an enantiomeric
excess (ee) of the (S) α-amino acid.
R vs. (R)
R refers to a variable side chain, radical, or residue, for example,
R–CH2Br
(R) and (S) are stereochemical terms, referring to clockwise and counterclockwise
orientations, respectively. According to The ACS Style Guide, (R) and (S) are italicized and
placed inside parentheses, for example,
The reaction leads to the (R)-amide.
Before we consider excerpt 4G, we fi rst walk you through the asymmetric
Strecker reaction (scheme 4.1). (The authors did not include a similar scheme
in their article because the reactions depicted in scheme 4.1 are familiar to
their audience.) First, note the use of compound labels in scheme 4.1. For clarity, we use the same labels that are used in excerpt 4G. The synthesis begins by
reacting a chiral primary amine, (R)-phenylglycine amide (R)-1, with an aldehyde 2. (We use a generic aldehyde in scheme 4.1; excerpt 4G uses pivaldehyde.) The product yields an imine that retains the chiral carbon (shown with
an asterisk). The imine is reacted with NaCN in acetic acid (HOAc) to form a
pair of diastereomeric amino nitriles, each with two chiral carbons. Following
hydrolysis, the nitriles are converted to a pair of diasteromeric α-amino acids,
(R,S)-3 and (R,R)-3. Recall that diastereomers, unlike enantiomers, have different physical properties and can be separated based on these differences.
(R,S)-3 is ultimately separated from (R,R)-3 and converted to the (S)-α-amino
acid (not shown).
With this in mind, consider Table 1 in excerpt 4G. The authors include only
the initial reactants (R)-1 and 2 and the final products (R,S)-3 and (R,R)-3 in their
142
The Journal Article
Scheme 4.1
H
N
*
CHPhCONH2
H
Ph
O
C*
CONH2
+
R
N
HOAc
C
H
H
R
–H2O
(R)-1
2
C
H
(R)-imine
H
N
NaCN, HOAc
*C
R
H
*
CHPhCONH2
N
*C
+
H
CN
(R,S)-amino nitrile
N
H3O+
*C
R
CN
R
H
H
*
CHPhCONH2
(R,R)-amino nitrile
H
*
CHPhCONH2
N
*C
+
COOH
H
*
CHPhCONH2
COOH
R
H
(R,S)-3
(R,R)-3
table. The arrow (↓) following (R,S)-3 indicates that (R,S)-3 preferentially precipitates out of solution, leaving (R,R)-3 in solution, and successfully separating the
two diastereomers.
Schemes
Schemes are used to illustrate progress in a chemical reaction (see chapter 16).
As you read the rest of the table and text in excerpt 4G, you will see that the
authors tried a number of different reaction conditions to maximize the yield of
(R,S)-3, the diastereomer that is ultimately converted to the (S) α-amino acid.
Writing the Results Section
143
(These final steps are not included in excerpt 4G, but if you are interested, the
full article is included at the end of chapter 2.) The text describes these efforts,
following the order of the entries in Table 1. First, different solvents were tried
beginning with methanol (entry 1). Next, various alcohol mixtures were tried,
but yields dropped (entries 2–4). The yield improved slightly when water was
mixed with methanol (entry 5); hence, water alone was tried at different temperatures (entries 6–9). This truly is a story of scientific discovery! The readers learn
both what did not work and what did. This approach is quite common in papers
describing organic synthesis.
Scientific Terms (excerpt 4G)
Diastereomer
A compound with two stereocenters where one
stereocenter is the same and one is different from its
isomer (e.g., (2R, 3R)-1 and (2R, 3S)-1 are diasteomers);
diastereomers have different physical properties
Diastereomeric excess (dr) An excess of one diastereomer in a reaction that leads to a
pair of diastereomers (e.g., 90% (2R, 3R)-1 and 10% (2R, 3S)-1)
Enantiomeric excess (ee)
An excess of one enantiomer in a reaction that leads to a
pair of enantiomers (e.g., 90% (2R, 3R)-1 and 10% (2S, 3S)-1)
Enantiomer
A nonsuperimposable mirror image of a molecule (e.g., (2S,
3S)-1 and (2R, 3R)-1 are enantiomers); enantiomers have
the same physical properties
Racemic mixture
An equal (50:50) mixture of two enantiomers
Exercise 4.18
Given the background provided on the asymmetric Strecker reaction, complete
the following tasks as you read excerpt 4G:
a. The goal of this reaction is to maximize the preferential crystallization
of (R,S)-3. Several different attempts were tried; some worked and some
did not. How do the authors share this process of discovery with the
reader? Include what was tried fi rst and what ultimately succeeded in
your answer.
b. Let’s pretend you are a member of Boesten’s research group. You were the first
to tackle this reaction. You intuitively chose water as the solvent (at 70 °C)
and let your reaction run for 24 h; these turned out to be the ideal conditions. Over the next several months, you tried other solvents and reaction
conditions, but never achieved better results. Would you still write the story
as it appears in excerpt 4G? Explain why or why not.
144
The Journal Article
c. How do the authors organize the results in Table 1? Argue for or against reorganizing Table 1 by percent yield (lowest to highest).
d. How do the authors highlight trends in their text without repeating the data
in Table 1? Give an example.
e. Excerpt 4G describes the synthesis of (R,S)-3, a critical intermediate in the
synthesis of the α-amino acid (S)-tert-leucine. The article goes on to present
several additional sets of results. We have summarized these below, but in a
scrambled order. Propose a logical order of presentation for these findings.
Justify your proposed order.
1. An X-ray structure of (R,S)-3, confirming its absolute configuration
2. A statement that points out that further examples of this reaction
are under investigation using (R)-phenylglycine amide with different
aldehydes
3. A graph that shows how the formation of (R,S)-3 depends on reaction time
(0.5–30 h)
4. A description of the synthetic steps taken to convert (R,S)-3 to the desired
product (an α-amino acid)
5. Results from an alternate synthesis of an intermediate amino nitrile
(similar to (R,S)-3) that uses a ketone as a reactant instead of the
aldehyde 2
Excerpt 4G (adapted from Boesten et al., 2001)
The asymmetric Strecker reaction of (R)-phenylglycine amide 1, pivaldehyde 2,
and HCN generated in situ from NaCN and AcOH was studied (Table 1). Amino
nitriles (R,S)-3 and (R,R)-3 were obtained in 80% yield in a ratio of 65:35 by stirring
an equimolar mixture of 1 (as AcOH salt) with 2 and NaCN in MeOH overnight at
room temperature, followed by evaporation of the solvent (entry 1). The diastereomeric ratio (dr) of (R,S)-3 and (R,R)-3 was determined by 1H NMR on the basis of the
relative integration between the t-Bu signals at 1.05 ppm for (R,S)-3 and 1.15 ppm for
(R,R)-3. . . .
Because in methanol crystallization of amino nitrile 3 did not take place, first the
solvent was varied in order to attempt to fi nd conditions for a crystallization-induced
asymmetric transformation. At a MeOH/2-PrOH ratio of 1/9, the amino nitrile (R,S)-3
was isolated in 51% yield and dr 99/1 (entry 2). Other combinations of alcoholic solvents
failed to lead to a higher yield of precipitated (R,S)-3 in high dr (entries 3 and 4). On
further screening of solvents, it was observed that upon addition of H 2O to the methanol solution selective precipitation of amino nitrile (R,S)-3 occurred giving (R,S)-3 and
(R,R)-3 in a ratio of 81:19 and 69% yield (entry 5). The asymmetric Strecker reaction was
further studied in H 2O alone using temperature as a variable. The results of these experiments are given in Table 1 (entries 6–9). After addition of NaCN/AcOH at 23–28 ºC
Writing the Results Section
145
to (R)-phenylglycine amide 1 and pivaldehyde 2 in H 2O, the mixture was heated to the
indicated temperatures.
Table 1. Asymmetric Strecker Reactions of (R)-Phenylglycine Amide 1 and Pivaldehyde 2
Ph
Ph
O
+
H
H2N CONH2
(R)- 1
solvent
MeOH
2
MeOH/2-PrOH, 1/9
3
2-PrOH
4
CONH2
HN
H
CN
HN
+
H
(R,S)- 3
2
entry
1
NaCN, HOAc
solvent, time, temp
Ph
c
c
2-PrOH/t-BuOH, 4/1
c
CONH2
CN
(R,R)-3
temp (ºC)
time (h)
yield (%)a
dr (R,S)-3/
(R,R)-3b
rt
20
80
65/35
rt
22
51
99/1
rt
22
84
88/12
rt
20
65
96/4
5
MeOH/H 2O, 35/1
rt
20
69
81/19
6
H2O
55
24
81
85/15
7
H 2O
60
24
84
96/4
8
H 2O
65
24
84
98/2
9
H 2O
70
24
93
>99/1
a
Isolated yield after evaporation of the solvent (entry 1) or filtration of precipitated amino nitrile 3
(entries 2–9).
b
The diastereomeric ratio was determined by 1H NMR spectroscopy.
c
Ratio in v/v.
4D Writing on Your Own: Tell the Story of Scientific Discovery
Identify the major trends that you will highlight in the text of your Results section. If
applicable, decide how you will highlight unexpected results and/or compare important
findings.
Using as guides (1) your gathered data and notes, (2) your sequenced sets of results and
graphics, (3) figure 4.1, and (4) chapter 16, write the text for your Results section. Start with
the first move (set the stage by transitioning from the Methods section and referring to a
graphic) and then continue with the second move (tell your story of scientific discovery).
Be sure to follow a logical sequence of events as you tell your story.
146
The Journal Article
Part 2: Analyzing Writing across the Results Section
In examining Results sections move by move, we looked at how authors refer
to figures and tables, how they use compound labeling, and how they highlight
trends in the data. We examined how to report values below detection limits
and how to use R to consolidate reactions in a synthesis paper. In this part of the
chapter, we analyze a few writing conventions that are characteristic of the entire
Results section, including verb tense, voice, and word choice.
Past and Present Tense
Unlike the Methods section, which is written primarily in past tense, both past
and present tense are used in the Results section. In general, present tense is used
(1) to refer the reader to a figure or a graph and (2) to make statements of general
knowledge expected to be true over time. Consider the following examples:
Present Tense Used to Refer to a Figure
The experimental desorption isotherms . . . are presented in Figure 1. (From
Jozefaciuk et al., 2003)
Figure 1A shows the ECD chromatogram obtained for the skim milk. (From
Llompart et al., 2001)
Present Tense Used to Indicate Knowledge Thought To Be True over Time
Saponification of fats . . . facilitates the release of PCBs from fatty matrixes.
(From Llompart et al., 2001).
Pure crystals of 2,2-diphenyl-1-picrylhydrazyl, the stable, low-molecularweight free radical, contain about 2 × 1021 radicals/g. (Adapted from
Dellinger et al., 2001)
Present Tense and Past Tense
Use the present tense in the Results section to refer to a graphic and to make statements
about knowledge expected to be true over time; in other cases, use the past tense.
Past-Tense Verbs in Results Sections
The 15 most frequent past-tense verbs in Results sections, in order of frequency (based on
an analysis of 60 Results sections from ACS journals), are as follows:
1. observed
2. obtained
3. showed
4. found
5. gave
6. revealed
Writing the Results Section
147
7. produced
8. formed
9. prepared
10. studied
11. reported
12. catalyzed
13. used
14. led
15. resulted
Passive and Active Voice
Recall from chapter 3 that passive voice allows writers to remove the human subject from a sentence, allowing the writer to focus on the science rather than the
scientists. One way to test if a sentence is in passive voice is to see whether you
can add “by someone” to the end of it:
Passive
The mixture was stirred (by someone).
Not passive (not correct) We stirred the mixture (by someone).
In figure 3.3 (chapter 3), we reported the frequencies of passive voice in each section of a journal article. If you look back at figure 3.3, you will see that passive
voice is used more frequently in Methods sections than in Results (or Discussion)
sections. This distribution suggests that both active voice and passive voice are
used in Results sections. Past and present tense, when combined with active and
passive voice, form four different tense–voice combinations. Each combination
has its own function, several of which are illustrated in table 4.1.
Table 4.1 Common functions of different verb tense–voice combinations in Results sections.
Function
Tense–Voice Combination
Example
To describe specific
results in your work
Past–active
Other combinations of alcoholic solvents
failed to lead to a higher yield. (From Boesten
et al., 2001)
To describe specific
steps in your work
Past–passive
Initial HSSPME experiments were performed
using spiked skimmed and full-fat milk
samples. (From Llompart et al., 2001)
To state scientific
“truths” or
knowledge
Present–active
PCBs are more strongly retained in the
sample matrix as the fat content increases.
(From Llompart et al., 2001)
To refer to a figure
or table
Present–active
Figure 1 shows as an example the mass
spectrum of the PFBOA derivative of
methional. (From Vesely et al., 2003)
Present–passive
Experimental adsorption isotherms for the
RAMEB-treated soils are presented in Figure
1. (From Jozefaciuk et al., 2003)
148
The Journal Article
Exercise 4.19
Follow steps a–c as you examine sentences 1–5 below (adapted from Weston
et al., 2004):
a. Using table 4.1 as a guide, determine the function of each sentence (1–5).
b. Identify the verb tense and voice used in each sentence.
c. Decide whether the verb tense used is appropriate given the function of the
sentence. If the tense used is inappropriate, rewrite the sentence so that it is
more appropriate for a Results section.
1. This assumption is reasonable because the toxicity of pyrethroids to benthic
organisms is predictable from the equilibrium partitioning-derived pore
water concentration (8), and the pyrethroids in this study have Koc values
comparable to those of cypermethrin (10).
2. A toxicity unit (TU) approach was used to identify pesticides potentially
responsible for observed toxicity.
3. Esfenvalerate concentrations are ≥0.5 TU in five samples.
4. Sediments of the tailwater ponds not only have the highest concentrations of
many pesticides but also prove to be highly toxic.
5. TU calculations for samples not toxic to C. tentans are shown in Table 3.
Use of “We”
Historically, the use of we (and other personal pronouns, e.g., I and our) in scientific writing has been controversial. Those opposed to the use of we argue that
it makes the writing sound less objective; hence, many scientists (particularly
1.00
1900–1949
1950–1989
1990–2006
"we"/"the"
0.75
0.50
0.25
0.00
Anal. Chem.
J. Org. Chem.
J. Phys. Chem.
Figure 4.2 The number of documents using we at least once (relative to the
number using the) over three time periods, determined using the ACS Journals
Search. (Note: J. Phys. Chem. includes J. Phys. Chem. A and B after 1996.)
Writing the Results Section
149
analytical chemists) have been taught to avoid we entirely. This trend is reflected
in the published literature. For example, figure 4.2 shows the number of articles that included the word we (normalized against the number of articles that
included the word the) in three different chemistry journals during three time
periods. Until 1990, analytical chemists used we far less frequently than their
organic- and physical-chemistry colleagues. Today, however, we appears at least
once in more than 85% of the documents published in these three journals.
“We” in the R&D Section
In a computer-based analysis of 60 Results and Discussion sections, the word we occurred
only 3 times per 1000 words. Thus, its use is quite rare.
The most compelling reason to use we in the Results section is to highlight a decision
or choice made while conducting your work.
The ACS Style Guide advises against using phrases such as “we believe”, “we feel”, and
“we can see”.
Despite its increased frequency over time, the use of we is still restricted. In
the Results section, where data are to be presented as objectively as possible, we
is generally not used in the first move (e.g., see excerpts 4D and 4E). Recall that
the purpose of the opening move is to remind readers of research methods, not
to draw attention to the researchers themselves; thus, we should be avoided when
describing work done in the past (e.g., X was measured is preferred over We measured X). Alternatively, we is used (sparingly) in the second move of the Results
section, where authors tell their story of scientific discovery. We can be used
to highlight a (human) decision or choice made during the course of the work.
Consider the following four examples:
150
■
In MALDI-MS, this challenge is overcome by coadding individual spectra.
We have adopted a similar approach to achieve reproducible SERS spectra.
(Adapted from Jarvis and Goodacre, 2004)
■
After injection of the methanol/water extract of kelp powder and kelp powder
spiked with 0.5 µg mL –1 of As(III), DMA, MMA, and As(V), we observed an
overlap of DMA and phosphate ribose. We therefore decided to change the
mobile phase. (From Almela et al., 2005)
■
Modification typically takes advantage of electrostatic interactions between
charges on the surface of the macromolecules and the polar headgroups of
surfactants. We reasoned that the host-guest interactions at the nanoparticlesolution interface investigated in this work could be used for similar purposes. (From Liu et al., 2001)
■
We have defined our sets of compounds for cross-comparison more broadly
than in previous studies. (From Vieth et al., 2004)
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The ability to use we appropriately comes only from reading the literature and
growing accustomed to the convention. As we’ve said before, many aspects of
scientific writing are not right or wrong; they are simply conventional or unconventional. It is not incorrect to use we frequently in the Results section; it is simply
not customary for experts to do so. To sound like an expert, you must learn the
convention.
Exercise 4.20
Consider the most compelling reasons for using we in a Results section. For
each passage below, decide whether the use of we is appropriate. Explain each
decision.
a. The results for the As and Pb concentrations we obtained for the 83 samples
are reported in Table 3. We note from Table 3 that the range of As and Pb
concentrations in the two populations is quite distinct.
b. We use the term K D, the distribution coefficient, in the following discussion,
although equilibrium may not have been achieved in all cases.
c. To reduce the problems of ligand-specific bias, we developed a modified rating for each molecule. We have called this corrected score the multiple active
site correction rating (MASC).
d. Within the reference group, we found that the mean oxidative damage for
smokers was significantly higher than that for nonsmokers.
e. At the end of each experiment, we measured the release of adsorbed alkenes
from air–water interfaces.
Use of “Respectively”
The word respectively (meaning “separately, in the order specified”) often appears
in science writing and can be used to make your writing more concise. Generally,
respectively appears at the end of the sentence; on rare occasions, however, it
appears within the sentence. Note, too, that when two or more items have the
same unit, the unit is stated only once.
■
The concentrations of 2-ABP, 3-ABP, and 4-ABP in PPD were estimated at 70,
310, and 500 ppb, respectively.
■
The turnover of 2-propanol and tosylate must exclusively take place via equilibria 5 and 6, respectively.
■
Assuming that the sample volume of seawater is 5 L, and the chemical recovery is 70%, the 239Pu and 240Pu concentrations in the final solution (~0.7 mL)
could be approximately 10.5 and 1.9 fg/mL, and U and Pb concentrations
would be approximately 15 and 1 µg/mL, respectively.
Writing the Results Section
151
■
Curves 1–3 correspond to film thicknesses of 10, 25, and 50 nm, respectively,
on a water–ice substrate that is 100 nm thick.
Compare the following sentences with and without the word respectively.
Less concise A was measured at X ºC, B was measured at Y ºC, and C was
measured at Z ºC.
More concise A, B, and C were measured at X, Y, and Z ºC, respectively.
In these examples, you can see how the word respectively helps achieve conciseness. More important, it aids clarity. By grouping values together, trends in the
data are easier to discern. To ensure that the correct meaning is conveyed when
using respectively, it is crucial that the order of the first set of items (e.g., A, B, C)
parallels the order of the second (e.g., X, Y, Z).
Respectively
See appendix A.
Exercise 4.21
Practice using respectively by rewriting each of the following passages to include
the word, when appropriate. If respectively cannot be appropriately introduced
into the passage, indicate “no change needed”.
a. The extrapolated FH parameters for infinite molar volume are plotted in
Figure 7, while the coefficients A are plotted in Figure 8. (Adapted from
Schwahn and Willner, 2002)
b. The conductivity increased by 0.5% in trial 1, 5.6% in trial 2, and 10.1% in
trial 3.
c. Ion intensities for m/z 29, 45, and 83 indicate that the Nafion membrane
discriminates in favor of methanol by a factor of 67 relative to chloroform
and ethanol by a factor of 55 relative to chloroform, assuming equal analyte
responses. (Adapted from Creaser et al., 2002)
d. For the low-energy transition, the origins are located at 626.6 nm in 1,
626.1 nm in 2, and 627.6 nm in 3. (Adapted from Spanget-Larsen et al.,
2001)
e. The reacting system as a solute was solvated in boxes containing 396 molecules of H2O (approximate dimension of 20 Å × 20 Å × 30 Å), CH3OH
(approximate dimension of 27 Å × 27 Å × 40 Å), and THF (approximate
dimension of 33 Å × 33 Å × 49 Å). (Adapted from Xue and Kim, 2003)
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Quantitative Language
As mentioned above, a Results section is descriptive, not interpretive. At times, the
difference between description and interpretation can be subtle; this difference is
often a matter of word choice. One way to keep your Results section descriptive is
to use precise language. By avoiding overly positive or negative words that are not
particularly precise, such as excellent, very good, or poor, and using more neutral
terms instead, such as high or low, you can maintain a descriptive tone in your
Results section. Even better, you can replace qualitative terms with more precise,
quantitative values. Consider the following examples:
Vague
Heating the mixture to 93 °C gave very good yields.
Better
Heating the mixture to 93 °C gave high yields.
Even Better Heating the mixture to 93 °C gave a 98% yield.
Vague
Better
The solution was very acidic.
The pH of the solution was 1.2.
Exercise 4.22
Rewrite the following passages so that the language is more descriptive than
interpretive. Feel free to “invent” measured data or details if you think that they
will help.
a. Because of the high acidity of the water, samples were collected in an appropriate container.
b. The cells were suspended in MSM, which gave good results.
c. Although GC/MS has been used on similar samples before, our preconcentration technique afforded a significant increase in sensitivity for the brominated compounds.
Use of “Very”
One of the most overused words by inexperienced writers is the word very. Some
scientists would argue that all instances of the word very should be eliminated
from journal articles because its use contributes to wordiness, minimizes objectivity, and indicates a lack of precision on the part of the writer. Nevertheless, very
is observed in the chemical literature, although infrequently. In excerpts 4A–4G,
it appears only twice:
Table 1 shows that the method provides very good reproducibility, with coefficients of variations for monitored aldehydes below 5.5%, except for (E)-2nonenal. (From excerpt 4A)
Writing the Results Section
153
As pure RAMEB sorbs a very high amount of water (ca. 1 g g–1 at p/p0 = 0.99),
an increase in water sorption was expected after RAMEB addition to all
soils. (From excerpt 4D)
Very Rare
Be careful not to overuse the word very in your own writing.
Exercise 4.23
Consider the use of very in the following passages. In which passages is very
necessary? In which passages is very most appropriate? What word substitutions
could be made for more precise writing?
a. Consequently, the voltage required was very high and as a result . . .
b. The spectrum of maltohexaose is very similar to that of . . .
c. Additional experiments were carried out, some of which yielded very surprising results.
d. Alkanes are also very inert to alcohols and ketones.
e. Because low-molecular-weight hydrocarbons are volatile and very poorly
soluble in water . . .
f. Because the rates of reaction were very slow . . .
g. The gel filtration experiments confirmed that very little Zn2+ was released . . .
h. The rate constants for the slowly and very slowly desorbing fractions were . . .
i. When BINAP or DPPF as a ligand was used, the yields were very low.
Scientific Plurals
The word data is commonly misused by writers; the mistake involves using data
as a singular noun. In nearly all instances, the word data is plural and should be
used with a plural verb:
Incorrect Data is . . .
Correct Data are . . .
Until you become more familiar with data being plural, you may read over a passage using data with a singular verb and not even notice the error (e.g., “data
shows” sounds correct to many native English speakers). It is difficult to catch a
mistake that does not sound wrong. In fact, many chemists use the word data as
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singular when speaking; it is only in writing, when there is more time for reflection and revision, that they correct themselves. A trick that may help you catch the
mistake in your own writing is to mentally replace the word data in your sentence
with a common plural word. For example, “The data shows a strong trend” may
not sound wrong to you, but “The values shows a strong trend” likely does. (In both
cases, “shows” should be “show.”) The singular form of data is datum, but the word
datum is rarely used; a single point of data is typically referred to as a data point
(rather than a datum). If the term data set is used instead of data, the singular verb
form is correct (e.g., “The second data set confirms this trend.”). Some correct uses
of data, with plural and singular verb forms, are shown in table 4.2.
Data
In nearly all instances, the word data is plural. The singular form, datum, is rarely used. The
word data is almost always used with a plural verb:
Incorrect Data is . . .
Correct Data are . . .
In addition to the word data, other scientific plurals are often problematic for novice writers. Table 4.3 includes a list of confusing singular and plural word forms.
Table 4.2 Uses of data in the literature (identified using the ACS Journals Search).
Data with a Plural Verb
These data show . . .
The data imply . . .
The data were biased by . . .
These data are supported by . . .
The data suggest . . .
The data reveal . . .
Data with a Singular Verb
The profile suggests that the data (set) is well converged.
Data Followed by a Singular Verb That Agrees with a Different Noun
Inspection of the data reveals . . .
A complete set of data is available.
A key feature of the bond length data is . . .
Writing the Results Section
155
Table 4.3 Singular and plural forms of common scientific words
(adapted from The ACS Style Guide: Coghill and Garson, 2006, p 128).
Singular Form
Plural Form a
apparatus
apparatus, apparatuses
appendix
appendixes, appendices
bacterium
bacteria
basis
bases
criterion
criteria, criterions
formula
formulas, formulae
fungus
fungi, funguses
index
indexes (indices if mathematical)
matrix
matrixes (matrices if mathematical)
medium
media, mediums
spectrum
spectra, spectrums
a. When more than one plural form is recognized, the preferred plural form is
given first.
Scientific Plurals
See appendix A.
Exercise 4.24
The following sentences may contain one or two errors with regard to singular and plural forms of words. Decide whether each sentence contains errors. If
it does, correct the sentence. If the sentence is correct as written, indicate “no
change needed”.
a. The HSSPME technique is most applicable for volatile analytes contained in
complex matrices.
b. As shown in Table 3, the data was highly reproducible with relative standard
deviations of less than 3% in all cases.
c. The mass spectrum (Figures 2 and 3) was collected in the selective ion monitoring (SIM) mode.
d. The criteria used to determine when trichloroethylene (TCE) had equilibrated between the solution and headspace was a change in headspace concentration of less than 5% over a 30 min period.
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e. The basis for our decision was the demonstrated inertness of PTFE toward
uptake of organics.
f. More data are needed to determine whether microbes significantly influence
the fate of selenium in this system.
4E Writing on Your Own: Practice Peer Review
Before you engage in authentic peer review, practice the peer review process. Imagine that
a colleague has asked you for feedback on a draft of a Results section. See “Peer Review
Practice: Results Section” at the end of this chapter for a copy of the draft, background
information, and instructions.
4F Writing on Your Own: Fine-Tune Your Results Section
By now, you should have made progress writing your own Results section by completing
the preceding Writing on Your Own tasks. When you have a good draft of your Results
section (having set the stage, move 1, and told your story of scientific discovery, move 2),
it is time to revise and edit your Results section as a whole. Focus on each of the areas
specified below while you reread your written work. Refer to chapter 18 to guide you in the
revision process.
1. Organization of text: Check your overall organizational structure. Did you follow the
move structure outlined in figure 4.1 and include appropriate subheadings? Have you
referred the reader to a figure or table at the end of move 1? Have you included at least
one of the following: important findings, trends, and unexpected results?
2. Audience and conciseness: Are you writing for an expert audience, leaving out
unnecessary details? Have you answered the question “What did you find?” as a way to
focus on description (rather than interpretation)? Find at least three sentences that can
be written more clearly and concisely. Are there sentences that could be made more
concise by using the word respectively? If the word we is used, check to see if it is used
correctly. Replace such words as excellent, very good, or poor with more precise words
or phrases.
3. Writing conventions: Check to be sure you have used voice and tense correctly (see
table 4.1). Are your graphics formatted correctly? Refer to chapter 16 to review formatting conventions.
4. Grammar and mechanics: Check for typos and errors in spelling, subject–verb agreement, and punctuation. Be sure that you have used troublesome scientific plurals (e.g.,
data) correctly.
5. Science content: Have you correctly conveyed the science in your work? Have you used
words and units correctly? If asked, could you define all of the words that you have used
Writing the Results Section
157
in this section? Do you understand the results of your work? Include only the most
relevant, representative data. If possible, use the broad-to-narrow approach to limit the
amount of data that you present to tell your story.
After thoroughly reviewing your own work, it is a common procedure to have your work
reviewed by a peer or colleague. A “new set of eyes” will pick up mistakes that you can no
longer see because you are too familiar with your own writing. To facilitate the peer review
process, use the Peer Review Memo (on the Write Like a Chemist Web site) to assist you and
your peer reviewer. After your paper has been reviewed (and you have reviewed another’s
paper), consult the Peer Review Memo given to you by your peer reviewer to make final
changes in your Results section.
Finalizing Your Written Work
See chapter 18.
Chapter Review
As a self-test of what you’ve learned in chapter 4, define each of the following terms,
in the context of this chapter, for a friend or colleague who is new to the field:
blocked R&D
broad-to-narrow approach
compound labels
detection limit
graphics
integrated R&D
iterative R&D
representative data
sets of results
Also explain the following to a friend who hasn’t yet given much thought to writing a Results section for a journal article:
158
■
Main purpose of a Results section
■
Moves of a Results section
■
Relationship between text and graphics in a Results section
■
Differences between description (for a Results section) and interpretation (for
a Discussion section)
■
Circumstances in which the use of we could be acceptable in a Results section
■
Uses of the past tense and present tense in a Results section
■
Common irregular plural words used in scientific writing
■
Uses of the word respectively
■
Use of the word very in a Results section
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Additional Exercises
Exercise 4.25
Rewrite the wordy sentences below to make them more concise:
a. As can be seen from Table 1, any of the samples that had been passivated
with PVB, MA, and PVA were seen to exhibit a substantial increase in quantum efficiency upon UV irradiation. (33 words; goal = 22 words)
b. It is worth mentioning that, in some experiments, partial racemization of the
alcohol was detected. (15 words; goal = 11 words)
c. In order to obtain further insight into the ways that the polymer may have an
influence on the UV enhancement, several samples that had previously been
coated with different polymers were irradiated. (32 words; goal = 15 words)
Exercise 4.26
Reword the following passages using more precise language. Feel free to “invent”
measured data or details if you think that they will help.
a. Among methanolic extracts from four specialty mushrooms, only Dictyophora
indusiata (basket stinkhorn) showed very good antioxidant activity (2.26% of
lipid peroxidation).
b. During photo-Fenton treatment, diuron degradation is extremely quick, but
final byproducts are formed only slowly.
c. All chlorinated hydrocarbons were observed at similar concentrations.
d. The second fertilizer showed more promise for increasing crop yield than
the first.
Exercise 4.27
Look at the Results sections of three journal articles. Examine the authors’ use
of tense, voice, we, respectively, neutral and precise language, very, and scientific
plurals. Are their uses consistent with your expectations? Explain.
Exercise 4.28
How might the following text and table from a Results section be improved?
Modify both to be more in line with journal article expectations. Consult chapter
16 if necessary.
Writing the Results Section
159
Results
4-Methoxyacetophenone 3 crystals were obtained in 70% yield by reacting equimolar amounts of 1 and 2 at 35 ºC for 5 min (entry 1). Temperature was varied in 5 ºC
increments between 35–70 ºC (entries 1–8), with the greatest yield occurring between
45–70 ºC (entries 3–7). At 35 °C, the yield was 70% and at 40 °C it was 80%. From
45–70 °C, yield remained at 85%. The reaction was then studied at 50 ºC using time
as a variable (entries 4, 9–11). The greatest yield was achieved at 50 ºC and 10–15 min
reaction time (entries 9, 10).
Table 2.
O
O
+
a
O
O
AlCl3
O
O
O
+
CH 2Cl2
1
2
entry
temp (°C)a
time (min)
yield (%)
1
2
3
4
5
6
7
8
9
10
11
35
40
45
50
55
60
65
70
50
50
50
5
5
5
5
5
5
5
5
10
15
20
70
80
85
85
85
80
80
85
92
92
90
OH
3
The water bath was kept within 5 °C of the specified temperature for the specified time.
Exercise 4.29
Reflect on what you have learned about writing a Results section for a journal
article. Select one of the reflection tasks below and write a thoughtful and thorough response:
a. Reflect on how reading the excerpts in this chapter has influenced your scientific reading and writing abilities.
■
■
160
Give three examples of how reading and analyzing excerpts of Results sections has (1) improved your ability to write your own Results section and/
or (2) changed your approach to writing your own Results section. Explain.
If your research advisor were to give you a paper to read, how confident
are you that you would be able to read and understand the Results section
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of the paper? How has your experience reading and analyzing the excerpts
in this chapter made this task easier? Explain.
b. Reflect on the move structures of Methods and Results sections. (If necessary,
consult figures 3.1 and 4.1.)
■
■
■
■
How do the different move structures reflect the vastly different purposes
of the Methods and Results sections?
Which writing conventions do you associate with the different moves and
the different sections?
How do those writing conventions assist writers in achieving their
purposes?
Which moves were easier for you to write? Why?
c. Reflect on the numerous excerpts that you have read in this chapter.
■
■
■
Although excerpts 4A–4G come from different journals and report on
different types of chemical research, they share some common attributes.
What are their commonalities?
Which excerpt assisted you the most in writing your own Results section?
Why was it so helpful?
What new chemistry content have you learned as a result of reading these
excerpts?
Peer Review Practice: Results Section
Imagine that a friend has asked you to review a draft of a Results section written
for a paper about the decomposition of solid biowastes (yard and food wastes).
Such biowastes typically decompose through a process known as anaerobic (i.e.,
without oxygen) biodegradation. However, anaerobic biodegradation generally results in low methane yields (50–60% of the theoretical maximum). Your
friend’s research group is trying to boost methane production during degradation
by first exposing the waste to a process known as wet oxidation.
The research involves many steps. Your friend’s part in the project is to examine how wet oxidation (WO) affects the amount of volatile suspended solids in the
waste. Volatile suspended solids (VSS) are solids that can be converted to gases
during wet oxidation, thereby affecting the total mass of waste leftover to undergo
anaerobic biodegradation. The Results section draft below describes this part of
the research project.
Using parts 2 and 3 of the Peer Review Memo on the Write Like a Chemist Web
site, review the Results section draft. Provide specific suggestions in your memo
that can be used to improve the Results section. (The Results section below is
adapted from an original source, noted in the Instructor’s Answer Key.)
Writing the Results Section
161
Results
1
Wet Oxidation (WO) Treatment. As described in the Experimental section above,
2 WO experiments were carried out in a high-pressure autoclave with a tubular loop and
3 an impeller constructed at Risø National Laboratory (17). The autoclave was designed as
4 a cylindrical vessel (V = 1890 mL) made of Sandvik Sanicro 28 (27% Cr, 31% Ni, 3.5%
5 Mo, and 1% Cu) with an impeller that continuously pumped the liquid through the
6 tubular loop.
7
Raw yard waste and food waste were oxidized under the same conditions (except
8 for WO time) (Table 1), while the digested biowaste was oxidized under 4 different
9 conditions (A–D). Yard waste underwent WO at 185 °C for 15 min at 12 bar. Food waste
10 underwent WO at 185 °C for 10 min. The WO conditions for digested biowaste treat11 ments A, B, C, and D were 185 °C for 15 min at 0 bar, 185 °C for 15 min at 3 bar, 185 °C
12 for 15 min at 12 bar, and 220 °C for 15 min at 12 bar, respectively.
digested biowaste
temperature
time
oxygen pressure
pH before WO
pH after WO
VSS before WO (g/L)
VSS after WO (g/L)
VSS oxidized (%)
yard waste
food waste
A
B
C
D
185 ºC
15 min
12 bar
9.5
3.7
33
30
9%
185 ºC
10 min
12 bar
7.2
4.6
41
27
10 %
185 ºC
15 min
0 bar
8.3
7.3
21
19
9%
185 ºC
15 min
3 bar
8.3
6.6
21
18
14 %
185 ºC
15 min
12 bar
8.3
4.4
21
17
20 %
220 ºC
15 min
12 bar
10.1
6.4
21
13
32 %
Table 1. Wet Oxidation (WO) Conditions and Volatile Suspended Solid (VSS) Losses for Raw Yard
Waste, Raw Food Waste, and Digested Biowaste (Conditions A–D)
13
For all cases, the WO treatment will cause a pH drop from 1 to 5.8 units, with the
14 most pronounced decrease in pH at the highest oxygen pressure. Furthermore, table 1
15 shows generally that 9–20% of the VSS contained in the waste will be oxidized during
16 wet oxidation at a WO temperature of 185 °C. At a WO temperature of 220 °C, approxi17 mately 32% of the organic content will be oxidized during WO.
18
In light of the Kyoto agreements and the EU green electricity certificates, additional
19 technologies to enhance the methane yield from various wastes and to ensure a biologi20 cally safe digested product are needed. Wet oxidation has a higher techno-economical
21 feasibility as compared to other pretreatment technologies for anaerobic digestion due
22 to the low oxygen consumption for the presented WO conditions, the self-sustaining
23 character of the WO reaction, and the opportunity for heat and oxygen recovery. There
24 is still a need to establish the technical and economical benefits of the WO technology in
25 addition to methane and ethanol recovery from various biomasses and waste.
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5
Writing the Discussion Section
A Discussion section should be as satisfying to read as the
last chapter of a mystery novel. The groundwork is laid in the
Introduction section, technological tools are described in the
Methods section, evidence is revealed in the Results section, but
it is in the Discussion section where the mystery is solved.
This chapter focuses on the Discussion section, the last part of the standard IMRD
structure for a journal article. The Discussion section, as mentioned in chapter 4,
can stand alone or can be part of a combined Results and Discussion (R&D) section. In either case, it serves the same major purpose: to interpret the results of
the study. In this chapter, we analyze excerpts from various Discussion sections,
including those that accompany results presented in chapter 4 (excerpts 4B–4G).
Upon completion of this chapter, you should be able to do the following:
■
Organize a Discussion section following the major moves
■
Interpret your results (but avoid overinterpretation)
■
Describe the greater importance of your findings
■
Follow appropriate writing conventions
As you work through this chapter, you will write a Discussion section for your
own paper. The Writing on Your Own tasks throughout the chapter will guide
you step by step as you do the following:
5A Read the literature
5B Prepare to write
5C Draft your Discussion section
5D Practice peer review
5E Fine-tune your Discussion section
In the Discussion section of a journal article, authors interpret their data, address
why and how questions (e.g., Why was the reaction faster? How did the mechanism
proceed?), and, ultimately, extend their findings to a larger context (e.g., What value
will these findings have to the scientific community?). Ideally, the Discussion section explains the story revealed by the data, postulates reasons for the observed
behaviors, and furthers our fundamental understanding of the underlying science.
Although interpretation is the primary goal of the Discussion section, authors
must be careful not to overinterpret their data, misinterpret their results, overstate their assumptions, or stray too far from scientific evidence. The excerpts
selected for this chapter illustrate ways to avoid these pitfalls. Similarly, the
excerpts illustrate that the language of the Discussion section is typified by
restraint and understatement. Such words as fact, truth, and prove are rarely used
in a Discussion section. Hedging words, such as theory and evidence, are much
more common, as are such verbs as appear, indicate, seem, and suggest. By hedging, writers acknowledge that their knowledge is limited and will be subjected to
scientific scrutiny over time.
Hedging Words
Words that soften interpretations and suggest that interpretations are not absolute facts.
Common hedges in scientific papers include the following:
apparently
largely
possibly
should
appear
likely
potentially
suggest
can
mainly
presumably
support
could
may
probable
typically
generally
might
probably
would
indicate
possible
seem
Reading and Analyzing Writing
Chemists should seek to advance chemical science, understand the
limitations of their knowledge, and respect the truth. Chemists should
ensure that their scientific contributions, and those of the collaborators,
are thorough, accurate, and unbiased in design, implementation, and
presentation.
—The Chemist’s Code of Conduct (www.chemistry.org)
To begin the analysis of the Discussion section, we ask you to read and analyze the Discussion section from the article on the analysis of aldehydes in beer.
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Because this article uses a combined R&D section, we refer you to chapter 4 for
this excerpt (excerpt 4A). The bulk of the Discussion section begins after the subheading “Beer Analysis”, although a few discussion-like sentences appear before
this subheading.
Exercise 5.1
Read the “Beer Analysis” section in excerpt 4A and answer the following
questions:
a. What moves do you see in this excerpt? Propose a move structure for the
Discussion section, with at least one move for each paragraph.
b. Find the two instances of hedging in this section. Explain the purpose
of each.
c. What is the purpose of the concluding paragraph?
d. Why was this study conducted? Where in the Discussion section is this
reason stated?
5A Writing on Your Own: Read the Literature
Read and review the Discussion sections of the journal articles that you collected during
your literature search (begun with Writing on Your Own task 2C). Read these Discussion
sections to learn more about your topic and to find ways to describe and interpret your
findings. Examine how the authors applied their findings to a broader research context.
Identify articles that you want to cite in your paper, such as works that offer supporting or
conflicting evidence. Jot down careful notes as you read.
Analyzing Audience and Purpose
Two major purposes of the Discussion section are to interpret or explain results
presented in the paper and to propose broader implications of these findings.
Not surprisingly, each purpose is associated with a slightly different audience.
The interpretation of results, like the Results section itself, is typically written for
an expert audience. (Hence, the novice organic chemist is likely to have trouble
understanding the references made to “Strecker aldehydes” and the “Amadori
pathway” in excerpt 4A.) Alternatively, the broader implications of the work are
typically accessible to a scientific audience or even a general audience. This shift in
audience completes the hourglass structure of the IMRD format. The Discussion
section forms the bottom of the hourglass; it begins with a specific focus but
ultimately expands to offer a more general perspective.
Writing the Discussion Section
165
Discussion Section
Two major purposes of a Discussion section are to interpret results and suggest broader
implications of findings.
Exercise 5.2
Reread the Discussion section of excerpt 4A.
a. Find two sentences that are accessible to a scientific (or even general) audience and two sentences that are geared toward a more expert audience.
b. What are the purposes of these different sentences?
Analyzing Organization
As shown in figure 5.1, the Discussion section is organized around two major
moves: Discuss Specific Results and Conclude the Paper. The first move is divided
into two submoves. Submove 1.1 reminds readers about the result that will be
discussed, serving as a transition between the Results and Discussion sections.
Such a reminder is often not needed in a combined R&D section but is necessary
in a stand-alone Discussion section. Its purpose is to draw the reader’s attention
to a particular finding, not to restate all of the results. This submove is often
accomplished in only a few sentences.
Specific
1. Discuss Specific Results
1.1 Remind reader of results
Cite
relevant
literature
1.2 Interpret results
Repeat (as needed) for each set of results
2. Conclude the Paper
2.1 Summarize the work
2.2 Suggest overall implications/applications of the work
General
Figure 5.1 A visual representation of the move structure for a typical Discussion section.
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Submove 1.2 is the heart of the Discussion section; mechanisms are proposed,
results are elaborated, and/or the authors postulate why or how a particular behavior was observed. Whenever possible, references to relevant literature should be
included as part of this submove. In particular, references that provide additional
insights, refute an argument, or corroborate the findings at hand should be cited.
In this way, your work can be connected to a larger body of evidence, moving
toward the ultimate goal of scientific consensus.
Corroborate
To strengthen and support results or interpretations, using evidence from the literature.
The first move is reiterated as needed for multiple sets of results, ideally paralleling the order that was used in the Results section. As in the Results section, you
can use subheadings to help the reader locate the discussion for each result. If,
while writing the discussion, you question the logic of your sequencing, you need
to revise both the Results and Discussion sections to align them.
Align Results and Discussion
The order in which you present findings (in Results) and interpret findings (in Discussion)
should be parallel.
The second and last move of the Discussion section signals the conclusion of
the paper. A heading (Conclusions or Summary) can be used to demark this
section, or it can be identified by the phrase In conclusion or In summary at the
start of a paragraph. Move 2 is also divided into two submoves. Submove 2.1
provides a brief summary of the work, highlighting the take-home message(s)
of the paper. This is followed by a brief narrative (submove 2.2) that suggests
implications and/or applications of the work and addresses at least one of the
following questions:
■
What are the implications of the work?
■
What new insights were gained?
■
How has this work increased our fundamental understanding of the research
area?
■
What are the practical applications of this work?
■
How will the work affect society (e.g., industry, medicine, technology, the
environment)?
Writing the Discussion Section
167
To answer these questions, authors must look beyond the specific details of their
own work and focus instead on the broader goals of the research project. Attaining
this broader outlook can be challenging, especially for students who spend most
of their time focused on only a small part of a larger project. Over time, however,
your grasp of the broader picture will improve as you continue to read the literature, attend seminars and conferences, and read and write research proposals in
your area of research.
Signaling the Conclusion
The last part of the Discussion section is often signaled with phrases such as
In conclusion,
In summary,
Note that these phrases are always followed by a comma.
If a conclusion is included in a section of its own, it is often marked with a Conclusions
heading.
Take-Home Message
A sentence or two that summarizes the essential features of the work, that is, the information that you want your readers to “take home with them.”
Exercise 5.3
Consider the following sentences taken from Discussion sections. Although
these sentences are presented out of context, specify which submove you think is
accomplished in each. Refer to figure 5.1.
a. The stress promoters induced in the Pro-Tox (C) test indicated that Cr3+ could
cause changes in DNA topology. (From Plaper et al., 2002)
b. In summary, (R)-phenylglycine amide 1 is an excellent chiral auxiliary in
the asymmetric Strecker reaction with pivaldehyde or 3,4-dimethoxyphenylacetone. Nearly diastereomerically pure amino nitriles can be obtained
via a crystallization-induced asymmetric transformation in water or water/
methanol. (From Boesten et al., 2001)
c. However, available data for size-fractionated fi ne particulate matter indicate that PAH quinones, including 1,4-naphthoquinone,
5,12-naphthacenequinone, benz[a]anthracene-7,12-dione, and anthracene9,10-dione, are important organic components (41, 42). The detection
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of these molecular species that are similar in structure to semiquinonetype radicals supports the assignment of our EPR signals. (Adapted from
Dellinger et al., 2001)
d. Our findings suggest that the surface properties and pore structure of
minerals change dramatically upon RAMEB addition. (From Jozefaciuk
et al., 2003)
e. A possible explanation for this effect can be attributed to an increased
density and viscosity of the milk–NaOH phase when NaOH concentration
increases. (From Llompart et al., 2001)
f. Because it is known that humans exposed to different Cr3+ species
accumulate high levels of Cr3+ intracellularly (17), presented results may
have an impact on human intake of Cr3+ as a nutrition additive. (From Plaper
et al., 2002)
g. In conclusion, we have shown that PM2.5 contains stable radicals that can be
detected by EPR. The EPR parameters, persistence in air, and DNA-damaging
capacity of the PM2.5 radicals are similar to those of the radicals in cigarette
tar. (From Dellinger et al., 2001)
h. The data in this article are consistent with a wealth of evidence showing that
dietary Se consumed in excess of the Recommended Dietary Allowance lowers the risk of several important cancers (2, 14, 26, 27). (Adapted from Finley
et al., 2001)
Before we continue, we point out two additional submoves, associated with move
2, that are less common today than in the past: (1) indicate limitations of the work
and (2) suggest ideas for future work. Although neither submove is addressed
in this textbook, you will see both submoves in the literature, and, in many
disciplines, they are still quite common. Thus, as you prepare your paper, check
to see if these submoves are expected in Discussion sections in your targeted
journal.
5B Writing on Your Own: Prepare to Write
In accord with the major purposes of a Discussion section, determine if you have enough
information to (1) interpret your results, (2) explain the broader implications of your work,
and/or (3) apply your results to a larger, broader context.
Similarly, review the move structure of a typical Discussion section (figure 5.1).
Determine if you have enough information to develop all moves and submoves.
Gather together this information, in outline form or as notes, to prepare to write your
Discussion section.
Writing the Discussion Section
169
Analyzing Excerpts
With the audience, purpose, and organization of the Discussion section in mind,
we are ready to analyze excerpts of Discussion sections from the chemistry literature. We begin by analyzing the excerpts move by move and then examine a few
writing conventions common to the entire section.
Part 1: Analyzing Writing Move by Move
In this part of the chapter, we revisit the journal articles that were introduced in
chapter 4, where we focused on Results. Here we focus on the Discussion sections
of these articles. We examine how well the authors follow the move structure in
figure 5.1, how they interpret their results, and how they conclude their work.
Let’s begin with the excerpt on randomly methylated β-cyclodextrin
(RAMEB)-enriched soils in chapter 4 (excerpt 4B). The authors use an iterative
R&D approach: They state their first result (R1), pertaining to clay-rich soils, and
then immediately offer an interpretation (D1) of that result. This is followed by a
result and interpretation for clay-poor soils (R2D2) and a result and interpretation
for medium-clay-content soils (R3D3). Thus, the result–discussion sequence is
iterated three times. In each case, the discussion immediately follows the result;
hence, submove 1.1 (which reminds readers of the result) is not needed.
Iterative R&D
The iterative R&D approach and other combined R&D approaches are described in
chapter 4.
R1D1 focuses on clay-rich soils (for the full excerpt, see excerpt 4B). Recall that
the clay-rich soils did not show the expected behavior. All RAMEB-treated soils
were expected to adsorb more water than their untreated counterparts, but such
was not the case with the clay-rich soils. Let’s see how the authors interpret this
unexpected result.
R1 However, the isotherms for RAMEB-treated clay-rich S6 and S7 soils
showed lower adsorption than the original soils, which is illustrated for
S7 soil with 49% clay.
D1 This potentially indicates that RAMEB decreases the amount of wateravailable surfaces in clay-rich soils, similar to what was observed for pure
clay minerals (20).
The authors offer a single sentence to explain the result: RAMEB decreases the
number of water-binding sites available in clay-rich soils. The authors offer this
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interpretation cautiously (using the hedging phrase “potentially indicates”) and provide additional support for their position by citing an earlier publication. Moreover,
the authors do not overinterpret this finding. They present general evidence that
RAMEB physically interacts with the particle surface but, for example, do not go on
to speculate about specific RAMEB–soil binding interactions. To do so would constitute a hand-waving argument, an interpretation that lacks sufficient empirical
evidence. Although hand-waving arguments serve as useful constructs for scientists
to think and talk about their results, they should be avoided in scientific papers.
Hand-Waving Argument
An expression used among scientists that implies that a researcher is advocating a theory
or belief with little evidence to support it.
Hand-waving arguments should be avoided. Interpretations included in Discussion sections should be supported by data.
In R2D2, the authors focus on clay-poor soils. For continuity, the authors must
explain why, in contrast to clay-rich soils, clay-poor (sandy) soils do take up more
water when treated with RAMEB. Importantly, the explanation for less water
uptake in clay-rich soils and more in clay-poor soils must be consistent with each
other. They cannot argue, for example, that RAMEB both increases and decreases
the number of water-available sites on the soil. With that in mind, let’s see how
they explain the clay-poor soil results:
R2 In sandy soils (S1–S4), the water sorption markedly increased,
particularly at higher RAMEB doses, as is illustrated for S2 soil.
D2 This may be attributed to water sorption by free RAMEB, that is, RAMEB
molecules that did not interact with the sandy soils.
Restated, sandy soils have smaller surface areas; hence, fewer RAMEB molecules
interact with their surfaces. This leaves more free RAMEB molecules, which
adsorb the extra water. Aha! The authors have painted a picture of what may
be happening that is consistent with the results for both soil types. This logic is
continued in R3D3, the results and discussion for the intermediate-clay-content
soils, as illustrated in the following exercise:
Exercise 5.4
R3D3 offers the results and interpretation for the water-sorption behavior of the
medium-clay-content soil (S5). We include R3 below (slightly modified):
R3 For soil S5 of medium clay content (25%), the effect of RAMEB on water
sorption was small.
Writing the Discussion Section
171
a. Compose your own D3 in a way that is consistent with D1 and D2 above.
b. When you are done, check to see the authors’ D3 in excerpt 4B. How similar
is your interpretation (D3) to that of the authors? Explain.
Jozefaciuk et al. (2003) go on to present and interpret several other sets of results
that are not included here (e.g., the effects of RAMEB addition on surface area and
porosity). Then, they conclude their article (move 2) as follows:
Our results demonstrated that RAMEB strongly interacts with soils, modifying their
surface, pore, and aggregate properties. These effects can affect soil remediation
technologies
In these brief two sentences, the authors provide a take-home message (that
RAMEB strongly interacts with soils) and suggest an application of their work
(soil remediation). In our estimation, they clearly win points for conciseness!
Affect vs. Effect
See appendix A for more information on these easily confused words.
The next example (excerpt 5A) returns us to the analysis of PCBs in milk.
Recall that Llompart et al. (2001) (excerpt 4C) used HSSPME techniques to detect
PCBs in milk. Their stumbling block was the fat content. The original method
worked fine on skim milk, but the fat contained in nonskim milk trapped the
PCBs in the liquid phase (those pesky matrix effects!), rendering headspace (i.e.,
gas-phase) analysis of the PCBs disappointing at best. More promising results
were obtained when the milk fat was first saponified with base (NaOH), a process
that helps to release the PCBs from the fatty matrix.
Llompart et al. (2001), like Jozefaciuk et al. (2003), use a combined R&D section (the preferred format in Analytical Chemistry, the journal that published this
article). Their R&D section describes both preliminary tests and optimization
procedures. Results and discussion of the preliminary tests were presented in
excerpt 4C; results and discussion of the optimization procedures are presented in
excerpt 5A. The optimization process used a factorial design in which five experimental parameters were systematically varied and tested to improve the saponification technique. These variables included the concentration of NaOH, the volume
of NaOH, the extraction and stirring times, and the kind of SPME fiber used.
Preference for Combined R&D Sections
The ACS journal Analytical Chemistry prefers a combined R&D section. As stated
in its authors’ guide, “In most cases, combining results and discussion in a single
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section will give a clearer, more compact presentation” (Anal. Chem. 2007,
79, 390).
As you read through the R&D section in excerpt 5A, you will notice that equal
time is not given to the Results and Discussion sections; more emphasis (and text)
is given to the Results. In a few instances, the authors offer an explanation (e.g.,
why the filter type was important only for the lighter PCBs and why, for some
PCBs, the concentration of NaOH showed a negative effect), but for the most
part, the focus is on the results of the optimization tests. Such an approach is not
unusual for an analytical paper whose major purpose is to improve an analytical
method. Results that demonstrate increased efficiency, detection limits, and/or
accuracy are the major reasons for doing such a study; hence, evidence that the
new technique works is emphasized over why it works.
Exercise 5.5
Read excerpt 5A. Which factors were the most important in the optimization
procedure? How are these factors emphasized in the text?
Excerpt 5A (adapted from Llompart et al., 2001)
Results and Discussion
[Continuation of excerpt 4C]
Optimization of the Saponification-HSSPME Process: Factorial Design. [The first three
paragraphs are omitted]
As can be seen in Figures 2 and 3, the agitation of the sample was the most important
factor for almost all the analytes. In all cases, this factor has a positive effect, and it appears
to be of increasing importance as the degree of chlorination of the PCBs increases. Also,
the extraction time was a significant factor for all the compounds, as might be expected.
On the other hand, the type of fiber was only important for the lighter PCBs, mainly for
PCB-28 and PCB-52. For these compounds, the PDMS-DVB fiber is more efficient than the
PDMS fiber. The effect of the fiber factor appeared negative (Figure 2) because PDMS-DVB
was selected as its low level (Table 1). For the highly chlorinated PCBs, the two fibers
tested seem to have similar performance, and this factor lacks statistical significance.
The volume of NaOH was also a significant factor for most of the compounds
but especially for the high-molecular-weight PCBs. The plot curvature of this factor
(Figure 3) shows optimum experimental settings that vary (2–3.5 mL) depending on
the PCBs to be extracted. The concentration of NaOH was only statistically significant
for PCB-105 and PCB-180. This factor showed a negative effect, which means that the
extraction efficiency decreases when the concentration of NaOH was at the high level.
A possible explanation for this effect can be attributed to an increased density and
viscosity of the milk–NaOH phase when NaOH concentration increases. This retards the
kinetics of the HSSPME process, and consequently, the extraction efficiency decreases.
Writing the Discussion Section
173
Its vs. It’s
See appendix A for more information on these easily confused words.
Llompart et al. (2001) conclude their article with a table (not shown) that
compares the amount of PCBs absorbed by the filter with and without saponification; results from performance evaluations and validation procedures are also
presented. Because the article does not end with a summary statement or broader
applications, it varies slightly from the move structure presented in figure 5.1.
In general, however, articles published in Analytical Chemistry follow the move
structure shown in figure 5.1. As indicated in the authors’ guide to Analytical
Chemistry, a separately demarked Conclusions section is preferred. The purpose of the Conclusions section is to offer interpretative remarks and present
broader implications of the work; the journal editors caution against repeating
information that is presented elsewhere in the article or abstract. As an example,
consider excerpt 5B, a Conclusions section from a different Analytical Chemistry
article. The conclusion follows the submoves in figure 5.1 by beginning with a
summary of the major achievement (improvements in the sensitivity of an electrochemical DNA sensor) and then going on to suggest possible applications of
this technique.
Excerpt 5B (adapted from Wong and Gooding, 2006)
Conclusion
Following our initial investigation on the transduction of DNA hybridization via
long-range charge transfer conducted in sequential steps, we have made significant
improvements with regard to sensitivity and ease of use via a single-step in situ electrochemical approach. Using the in situ approach, the DNA biosensor is able to detect target
DNA in the subnanomolar range within 1 h. Furthermore, the in situ detection scheme
is also able to differentiate between complementary, noncomplementary target DNA,
and even target DNA with single-base pair mismatches, including the most thermodynamically stable G-A mismatch, without requiring any additional stringency steps. This
new approach also has the ability of studying biological processes in real time and thus
allows the kinetic processes to be monitored. The good sensitivity, excellent selectivity,
and simplicity of use of the DNA biosensor make it more compatible for integrating with
on-chip PCR reactors than other DNA biosensors of which we are aware.
Exercise 5.6
Glance through six articles in a current issue of Analytical Chemistry.
a. How many articles use a combined R&D section rather than separated
Results and Discussion sections?
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b. How many articles include a separate Conclusions section?
c. Select two Conclusions sections in Analytical Chemistry. How well do they
adhere to the second move represented in figure 5.1?
We next consider the Discussion section that follows excerpt 4D concerning the
genotoxicity of Cr3+ in bacterial cells (Plaper et al., 2002). Recall from excerpt 4D
that three forms of Cr3+ were initially investigated: chromium chloride, chromium nitrate, and chromium oxalate. Chromium chloride and chromium nitrate
both induced stress promoters indicative of DNA damage, but chromium oxalate
did not. The authors also measured chromium accumulation in E. coli cells.
Chromium from chromium chloride and chromium nitrate was taken up by the
cells, but chromium from chromium oxalate was not. Finally, the authors examined how Cr3+ (from chromium chloride) affects gyrase, the enzyme that regulates the relaxation of supercoiled DNA. Gyrase inhibition was observed at CrCl3
concentrations >10 µM.
Plaper et al. (2002) use a stand-alone Discussion section, rather than a combined R&D section. According to the move structure in figure 5.1, a separate
Discussion section should begin with a brief reminder of a specific result or set of
results; this is essentially how Plaper et al. (2002) begin. The authors first remind
the readers about the study in general (in the first two sentences); then, in the
third sentence, they remind the readers specifically about the Pro-Tox (C) assay
with chromium chloride.
P1 Many studies have shown that not only Cr6+ but also Cr3+ cause damage
inside the cells. In this work, three Cr3+ compounds were examined for
their impact on genotoxicity and cell proliferation in vitro. Chromium
chloride added to E. coli strains in the Pro-Tox (C) test system induced
lacZ gene transcription from several stress promoters. (Adapted from
Plaper et al., 2002)
The paragraph goes on to interpret these fi ndings, indicating that DNA is a
target for Cr3+ inside the cell. The authors describe some of the stress promoters that were induced and frequently cite the literature to offer additional
insights and corroborating evidence. At the end of the paragraph, the authors
suggest possible causes for these inductions. Two references to the literature
support the suggestion that the hydroxyl radical may be the cause of the DNA
damage.
P2 Most of the latter were associated with different types of DNA damage,
indicating that DNA is one of the main targets for Cr3+ inside the
cell. The most prominent effect was on lacZ transcription from dinD
promoter, which responded to all types of DNA lesion. RecA promoter
Writing the Discussion Section
175
was also induced, indicating problems with DNA replication (37).
Additional evidence of DNA damage was the induction of merR and
osmY promoters. The induction of lacZ transcription from merR is not
surprising as merR is the promoter that responds to the presence of
the heavy metals such as cadmium and mercury (24). Moreover, it has
been shown that merR is induced by changes in DNA topology (26).
Changes in DNA supercoiling could also account for strong induction
of lacZ transcription from osmY promoter. The osmY stress gene usually
responds to hyperosmotic environmental conditions, but it can also be
regulated by changes in DNA topology, similarly to the proU operon
(10, 16, 39). In our test, there was also 5-fold induction from soi28, an
oxidative stress promoter responding to oxidative damage in the cells.
This induction could be caused by the hydroxyl radical produced in
the reaction between Cr3+ and hydrogen peroxide (22). The hydroxyl
radical is a known mediator of DNA damage, causing lesions to DNA
bases and to the phosphodiester sugar backbone (13). (From Plaper
et al., 2002)
Between vs. Among
See appendix A for more information on these easily confused words.
The first move is reiterated in each of the next two paragraphs. The second
paragraph initially reminds the reader about the negative results obtained with
chromium oxalate, both in the Pro-Tox (C) test and in the FAAS measurements
of E. coli cells. The paragraph goes on to interpret these results, suggesting that
the lack of induction by chromium oxalate is “probably due to the inability of
that compound to enter the bacterial cells.” Note that the authors do not speculate on how chromium chloride and chromium nitrate enter the cells, or on how
chromium oxalate might be excluded. Again, to do so would be hand-waving.
Their data show only that chromium concentrations are negligible in test cells
when chromium oxalate is used; their analytical probe (FAAS) does not provide
insights into the mechanisms of chromium transport.
P3
176
When E. coli test strains were treated with chromium nitrate, the
induction profile obtained was very similar to chromium chloride
profile (data not shown). The promoters that were induced indicate
that the action of Cr3+ was on DNA. However, none of the 13 stress
promoters responded to chromium oxalate at any of the concentrations
tested. . . . The lack of lacZ induction in the case of chromium oxalate
is probably due to the inability of that compound to enter the bacterial
cells. This was confirmed with FAAS measurements of total chromium
The Journal Article
concentrations in E. coli (Table 1). In cells treated with chromium
oxalate, concentrations of chromium were negligible. (Adapted from
Plaper et al., 2002)
The third paragraph focuses on the influence of Cr3+ on gyrase. The paragraph
begins by providing motivation for the gyrase experiments and reminds the
reader of the experimental results (that Cr3+ binds to gyrase and DNA and may
inhibit gyrase activity). Citing references to the literature for supporting evidence, the authors suggest that Cr3+ may be binding to the OH group in the active
site of gyrase, thereby causing the inhibition. An alternative explanation is also
provided.
P4 The stress promoters induced in the Pro-Tox (C) test indicated that
Cr3+ could cause changes in DNA topology and in this way also affect
proper DNA replication and transcription. For this reason, we examined
the influence of Cr3+ on gyrase, an essential enzyme that relaxes and
supercoils double-stranded DNA in bacterial cells. . . . We showed that
Cr3+ binds to gyrase as well as to DNA. Additionally, we showed that Cr3+
may inhibit the enzyme’s activity. . . . [T]he inhibition of gyrase activity
may well be a consequence of Cr3+ binding to the OH group of the Tyr in
the active site, preventing the enzyme’s interaction with DNA phosphate
groups (27). It is also possible that Cr3+ binds to some other part of the
enzyme and causes changes in the gyrase conformation so that Tyr122
is no longer available for interaction with DNA. (Adapted from Plaper
et al., 2002)
The conclusion of the work (move 2) is accomplished in the final paragraph of the
article. The conclusion is broad in scope, reiterating the take-home message that
Cr3+ can affect DNA. Implications of these findings are also suggested.
P5 Our results suggest that Cr3+ has an impact on DNA, DNA topology, and
consequently processes leading to cell growth and proliferation. This
could ultimately lead to the mutagenic and carcinogenic potential of
Cr3+. Because it is known that humans exposed to different Cr3+ species
accumulate high levels of Cr3+ intracellularly (17), presented results may
have an impact on human intake of Cr3+ as a nutrition additive. (Adapted
from Plaper et al., 2002)
Exercise 5.7
Refer to passages P1–P5 as you complete the following tasks:
a. Read over passages P1–P4. In each, find a group of two to three sentences
that together remind the reader of and interpret specific results.
Writing the Discussion Section
177
b. Do the authors present their interpretations as facts, or do they use more cautious language? Support your answer with words from the text.
c. Is the last paragraph (P5) accessible to a scientific audience (as opposed to an
expert audience), thereby completing the hourglass structure? What larger
implications do the authors present?
d. Let’s imagine that several studies (7–9) suggest that chromium oxalate cannot enter bacteria cells because of its size. (It is too big; the oxalate anion is
–OOC–COO –, significantly larger than either NO3 – or Cl–.) Add a sentence
or two to the end of the second paragraph (P3) to relate the current work to
these studies.
Audience
See chapter 1 for distinctions among expert, scientific, student, and general audiences.
Next, we analyze the Discussion section from Dellinger et al. (2001) regarding the toxicity of fine particulate. Remember that the authors postulated that
free radicals in PM 2.5 contribute to its toxicity (excerpt 4E). The authors provided evidence that PM 2.5 contains free radicals and that untreated extracts of
PM 2.5 induce DNA damage. However, DNA damage was not observed when free
radical scavengers or Fe3+ chelators were added to the PM 2.5 extracts. Taken
together, the data suggest that both free radicals and Fe3+ are involved in the
toxicity of PM2.5.
Dellinger et al. (2001) go a bit further and suggest that the free radicals in PM2.5
are also the ones in cigarette tar (semiquinones), and they propose a mechanism
by which this free radical can induce DNA damage (excerpt 5C). These suggestions are not mere speculation (which would constitute hand-waving) but are
corroborated by the literature. The literature on the health effects of cigarette tar
is extensive; hence, the authors build on this knowledge base. In this way, excerpt
5C represents a good example of how the literature can be used to provide deeper
insights into data.
Excerpt 5C also provides a good example of how prose can be used to guide
readers through a reaction cycle or mechanism. In this excerpt, a redox cycle
is described (reactions 1–5); the text accompanying the cycle points out which
reactions lead to the biologically damaging hydroxyl radical (reactions 1–3), how
Fe2+/Fe3+ may also be involved (reaction 3), and how the semiquinone radical is
regenerated in the cycle (reaction 4). The authors conclude their article by reiterating their findings and suggesting that their results may apply, more generally, to
the deleterious health effects associated with combustion-generated particulate
matter.
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Exercise 5.8
As you read through excerpt 5C, answer the following questions. To guide
your reading, we include structures for quinone, the semiquinone radical, and
hydroquinone:
.
O
O
OH
O
OH
OH
quinone (Q)
semiquinone radical (QH )
.
hydroquinone (QH2)
a. What is the purpose of the first sentence in excerpt 5C? Is this first sentence
consistent with the general move structure presented in figure 5.1?
b. In the first paragraph, the authors make the case that the radicals in PM 2.5 are
the same as those in cigarette tar (semiquinones). What evidence do they cite
for this interpretation? Do you find the evidence convincing? What if they are
wrong? Should the publisher issue a correction to the article?
c. The authors include a redox cycle in their Discussion section. The cycle
shows a way in which the hydroxyl radical (HO·) can be continuously produced from the semiquinone radical (QH·). Is this an original mechanism, or
one that the authors have included from the literature? How could you tell?
d. Recall that the authors point out, in the Results section, that both free radicals and Fe3+ may be the cause of DNA damage. Are both species implicated
in the proposed mechanism and accompanying text? In other words, is the
proposed mechanism consistent with their data? Explain.
e. In which paragraph does the second (and last) move begin? How can you
tell? The move is divided into two paragraphs. Which submove is accomplished in each paragraph?
f. The word we occurs two times in the penultimate paragraph. Rewrite these
sentences without we. Which do you like better? Explain.
Excerpt 5C (adapted from Dellinger et al., 2001)
[Continuation of excerpt 4E]
Discussion
The radicals in PM 2.5 have similar EPR g-values and line shapes to the radicals found
in cigarette tar (12, 18, 31, 33, 37). The cigarette tar radicals produce DNA damage that is
similar to that produced by PM 2.5. The cigarette tar radicals are a family of semiquinone
Writing the Discussion Section
179
radicals that are present in a dynamic hydroquinone (QH2), semiquinone (QH·), quinone
(Q) system (12, 18, 31, 33, 37). Our body of data leads us to propose that the radical
signals we report are also due to semiquinone-type radicals.
The sample sizes collected by our PM 2.5 sampling systems are insufficient to
conduct detailed chemical analyses. However, available data for size-fractionated fi ne
particulate matter indicates that PAH quinones, including 1,4-naphthoquinone, 5,12naphthacenequinone, benz[a]anthracene-7,12-dione, and anthracene-9,10-dione, are
important organic components (41, 42). The detection of these molecular species that
are similar in structure to semiquinone-type radicals supports the assignment of our
EPR signals.
A semiquinone radical (QH·) can lead to the production of the hydroxyl radical (HO·), as shown in reactions 1–3. QH· can reduce oxygen to form superoxide
(O2· –), reaction 1. Superoxide production leads to the formation of hydrogen peroxide (H 2O2), reaction 2, which, in turn, yields the biologically damaging hydroxyl
radical in a metal ion-dependent reaction, reaction 3. In addition, the quinone (Q)
produced in reaction 1 can be reduced back to QH· and further to the hydroquinone (QH 2) by reducing agents present in biological systems, as shown in reactions
4 and 5 (43).
.
QH
–
.
2O2
+
O2
Q
+
+
–
.
O2
+ O2
(2)
HO– + Fe3+
(3)
+
2H
H2O2
+
Fe2+
HO
Q + e– + H +
.
QH + e– + H+
QH
H2O2
.
.
QH2
+
+
H+
(1)
(4)
(5)
Reactions 1–5 establish a redox cycle (43) in which the hydroxyl radical is continuously produced from the radicals in PM 2.5. It is well documented that the hydroxyl radical causes DNA strand breaks (33).
The data shown in Figures 1–4 support the suggestion that PM 2.5 contains radicals
that, like those in cigarette tar, can reduce oxygen to superoxide, which then forms
hydrogen peroxide and, ultimately, the hydroxyl radical, as shown in reactions 1–3. Iron
and copper ions, which are the transition metals most frequently found in combustiongenerated particles (44) and also are ubiquitous in biological systems, could be involved
in reaction 3. . . .
In conclusion, we have shown that PM 2.5 contains stable radicals that can be detected
by EPR. The EPR parameters, persistence in air, and DNA-damaging capacity of the
PM 2.5 radicals are similar to those of the radicals in cigarette tar. Therefore, we propose
that the radicals associated with PM 2.5 include semiquinone-type radicals that, like the
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cigarette tar radical, can reduce oxygen to produce superoxide and ultimately produce
the DNA-damaging hydroxyl radical.
The results presented here suggest a new mechanism of toxicity for PM2.5 based on
sustained hydroxyl radical generation by the semiquinone radicals present in PM 2.5.
Because a substantial fraction of the fine particles in the atmosphere arises from
combustion sources (9), it is possible that the deleterious health effects associated with
PM 2.5 can be at least partially ascribed to radicals associated with combustion-generated
particulate matter.
Hyphenated Modifiers
Chemistry writing includes many two-word modifiers that describe nouns. Consider these
examples:
■
low-energy process
■
high-energy sites
■
bioremediation-accelerating effect
■
semiquinone-type radicals
■
3-fold induction
■
DNA-damaging capacity
■
combustion-generated particulate matter
(See appendix A.)
We complete our analysis of the Discussion section by examining two representative organic synthesis articles that appeared in Organic Letters and The
Journal of Organic Chemistry. These journals typically omit section headings
entirely (Organic Letters) or include only an Experimental Section heading at the
end of the article (The Journal of Organic Chemistry). Nevertheless, we can still find
the typical moves of a Discussion section in these seemingly “discussion-less”
articles.
We first consider the Demko and Sharpless article (2001) on the synthesis
of substituted tetrazoles from nitriles in water (excerpt 5D). This excerpt is particularly useful because it illustrates several types of content that authors typically discuss in synthesis papers. The authors begin by proposing two possible
mechanisms for the tetrazole reaction, a two-step mechanism and a concerted
mechanism. The mechanisms are presented in a scheme (Scheme 1). In the
accompanying text, the authors cite evidence for both mechanisms, highlight
salient features of the mechanisms, mention the results of kinetic studies, and
point out that the role of zinc metal is as yet unclear.
Writing the Discussion Section
181
Schemes
Schemes, like figures and tables, are a form of graphics. They are often used to depict proposed reaction mechanisms. A proposed mechanism, by its very nature, is interpretative;
hence, schemes are commonly found in Discussion sections.
For information on formatting schemes, see chapter 16. Also see exercises 5.9 and 5.10.
The authors go on to discuss several additional factors related to their synthesis, such as stoichiometric considerations (molar equivalents needed to ensure
that the reaction goes to completion), chief competing reactions and how they
might be minimized, and other reagents that might be successful substitutes in
the reaction. Finally, they discuss their efforts to scale up the reaction, taking it
from bench-scale to large-scale applications. Although some of these discussion
points are not interpretive in a formal sense, they are representative of common
topics in the Discussion section of a synthesis paper. Following typical organizational conventions, the authors conclude with a brief summary of the article and
suggest larger implications and applications of their findings (following the move
structure represented in figure 5.1).
Exercise 5.9
As you read through excerpt 5D, notice that the authors use a scheme to present
two proposed mechanisms for the reactions. Using this excerpt as an example,
propose a set of rules for formatting a scheme (see also chapter 16).
Excerpt 5D (adapted from Demko and Sharpless, 2001)
[Continuation of excerpt 4F]
Kinetic studies using the water-soluble nitrile 1i revealed first-order dependence in
both nitrile and azide and one-half order dependence for zinc bromide. The mechanism of the addition of hydrazoic acid/azide ion to a nitrile to give a tetrazole has been
debated, with evidence supporting both a two-step mechanism8b,21 (Scheme 1, eq 2) and
a concerted [2 + 3] cycloaddition 22 (Scheme 1, eq 3). Our mechanistic studies to date
imply that the role of zinc is not simply that of a Lewis acid; a number of other Lewis
acids were tested and caused little to no acceleration of the reaction.23 In contrast, Zn 2+
exhibited a 10-fold rate acceleration at 0.03 M, which corresponds to a rate acceleration
of approximately 300 at the concentrations typically used. The exact role of zinc is not
yet clear.
Empirically, we found that to ensure complete reaction one needs a 0.5 molar equiv
of the zinc salt (ZnX 2); however, in many cases, lower loadings of zinc may be used.24
The chief competing reaction is hydrolysis of the nitrile to the primary amide; therefore, in cases where the tetrazole-forming reaction is sufficiently fast, namely, with
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electron-poor nitriles, lower zinc loadings did not entail significant formation of the
amide byproduct. Other zinc salts such as zinc perchlorate and zinc trifl ate also work;
zinc chloride, while less expensive, led to more of the amide byproduct. Zinc bromide was chosen as the best compromise between cost, selectivity, and reactivity (see
Table 3).
Scheme 1
Two-step Mechanism
N
MN3
M
N
R
R
N
N +
N –
M
N N
R
N
N
(2)
Concerted Mechanism
N
N
N
MN3
R
R
N +
N –
N N
R
M
N
N
(3)
M
M = H, L n Zn, other metals
The process became even more attractive for large-scale applications when we found
that it could be run at higher concentration without sacrificing yield and without the
use of organic solvents in the workup or isolation phases. The resulting products were
spectroscopically identical by 1H NMR and 13C NMR to those synthesized by the general
method outlined below; however, the melting points were slightly lower.
In summary, we have demonstrated an exceedingly simple protocol for transforming a
wide variety of nitriles into the corresponding 1H-tetrazoles. By using zinc salts as catalysts,
we showed that water can be used as the solvent despite the relative insolubility of the starting materials. This discovery should facilitate the preparation of tetrazoles in the laboratory.
Topics of Discussion in a Synthesis Paper
■
a mechanism
■
kinetic (rate) vs. thermodynamic (energy) considerations
■
role of a catalyst
■
stoichiometry
■
competing reactions (and how to minimize them)
■
alternative reagents
■
efforts to scale up the reaction
Writing the Discussion Section
183
Which vs. That
See appendix A for more information on these easily confused words.
Exercise 5.10
Find out if your set of rules for schemes (generated as part of exercise 5.9)
applies to schemes in other articles. Check three articles in The Journal of Organic
Chemistry or Organic Letters to see if your rules hold true. In these articles, how
do the authors use compound labels and accompanying text to walk the readers
through the schemes?
Exercise 5.11
Browse through three Discussion sections of synthesis articles in The Journal of
Organic Chemistry. In addition to proposed mechanisms, make a list of other topics routinely addressed in Discussion sections.
Lastly, we consider Boesten et al. (2001) (excerpt 5E), which describes an asymmetric Strecker synthesis. Recall that the synthesis results in two diastereomers, which
can be separated based on their different solubilities in water. In exercise 2.14
(chapter 2), you were asked to decide where the Discussion section began in this
article. That exercise was more challenging than you may have realized. The article
presents numerous results, with only a few sections of integrated discussion.
Exercise 5.12
With these comments about the Boesten et al. (2001) article in mind, go back and
try exercise 2.14(f) again. Reexamine the Strecker synthesis article (at the end of
chapter 2) and assign R or D to the appropriate sentences and/or paragraphs.
Consider your answers to exercise 5.12. You will probably agree with us that
Figure 2 (in the Boesten et al. article), along with the paragraph that describes it,
is part of the discussion. We have reproduced the figure and its accompanying
text in excerpt 5E. Once again, the discussion focuses on a mechanism, although
in this case, the mechanism is presented in a figure rather than a scheme. (The
choice to use a figure or scheme is usually left to the authors.) The authors propose
a mechanism that includes a reaction intermediate (R)-4 and shows how (R,S)-3 is
produced preferentially over (R,R)-3. The text walks the reader through important
aspects of the mechanism, pointing out that, at room temperature, CN– attacks the
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re face of (R)-4 preferentially, producing (R,S)-3 in greatest yield. At elevated temperatures, because (R,S)-3 crystallizes out of solution more readily than (R,R)-3,
equilibrium favors the (R,S)-3 product. In a separate graphic (Scheme 1), the
authors go on to describe how (R,S)-3 is ultimately converted to the target molecule, (S)-tert-leucine. The article ends with a short paragraph that summarizes
the work, underscores its usefulness (“a practical one-pot” synthesis), and suggests
ways in which the synthesis can be applied to other target molecules.
The re Face
An sp2 carbon in which the three substituents are oriented clockwise according to CahnIngold-Prelog sequence rules.
1
N
H
3
clockwise
C
R
2
re face
Exercise 5.13
As you read excerpt 5E, complete the following tasks:
a. Explain why the imine intermediate in Figure 2 is labeled (R)-4 even though
it leads to the formation of (R,S)-3 and (R,R)-3. (Hint: Look at Table 1 of
Boesten et al. (2001) at the end of chapter 2.)
b. Typically, it is sufficient (and recommended) that you refer to a compound by
number only, after the number has been introduced. However, Boesten et al.
(2001) do not follow this rule in their final paragraph. Both (R)-phenylglycine
amide 1 and (S)-tert-leucine 7 are mentioned a second time using name and
number. Why you think that the authors do this, rather than simply using
1 and 7?
c. Imagine that you are a synthetic chemist and that you have successfully synthesized the compound ABC 5. Write a one- to two-sentence summary statement for your paper on the synthesis of 5 based on the following information:
1. the reaction is easy and involves only three steps
2. the reaction is inexpensive
3. the synthesis is a general one and can be applied to other compounds
4. the yields are good (>95%) with few side reactions
Writing the Discussion Section
185
Excerpt 5E (adapted from Boesten et al., 2001)
[Continuation of excerpt 4G]
Ph
CONH2
N
H
re-face
attack
HCN
Ph
HN
(R)-4
HCN
CONH2
CN
H
preferential
crystallization
(R,S)-3
Ph
HN
CONH2
CN
H
(R,R)-3
Figure 2. Crystallization-induced asymmetric transformation of
amino nitrile 3.
The observed diastereoselectivity in the asymmetric Strecker step via the crystallization-induced asymmetric transformation can be explained as shown in Figure 2.
Apparently, the re face addition of CN – to the intermediate imine 4 is preferred at room
temperature in methanol and results in a dr 65/35. At elevated temperatures in water,
the diastereomeric outcome and yield of the process are controlled by the reversible
reaction of the amino nitriles 3 to the intermediate imine and by the difference in solubilities of both diastereomers under the applied conditions.16,17 . . .
In summary, (R)-phenylglycine amide 1 is an excellent chiral auxiliary in the asymmetric Strecker reaction with pivaldehyde or 3,4-dimethoxyphenylacetone. Nearly
diastereomerically pure amino nitriles can be obtained via a crystallization-induced
asymmetric transformation in water or water/methanol. This practical one-pot asymmetric Strecker synthesis of (R,S)-3 in water leads to the straightforward synthesis of
(S)-tert-leucine 7. Because (S)-phenylglycine amide is also available, this can be used
if the other enantiomer of a target molecule is required. More examples are currently
under investigation to extend the scope of this procedure.19
5C Writing on Your Own: Draft Your Discussion Section
Write a complete draft of your Discussion section. Begin with an outline of your results and
interpretations, and then convert the outline to full sentences. Sketch out any schemes (or
figures) you plan to include, and draft the text that will accompany those schemes. End
your draft with a paragraph that concludes your paper and suggests the broader applications of your work.
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Part 2: Analyzing Writing across the Discussion Section
Here, we examine writing conventions that are common throughout the
Discussion section. We focus on tense and voice in addition to two word-choice
issues, the use of we and hedging words.
Tense and Voice
Both past tense and present tense are common in the Discussion section. The same
rule of thumb introduced in the Methods section applies to the Discussion section:
The work was done in the past, but knowledge exists in the present.
For example, Plaper et al. (2002) state that “three Cr3+ compounds were examined” (work done in the past) but that the “hydroxyl radical is a known mediator
of DNA damage” (knowledge that exists in the present). Similarly, the presenttense, active-voice combination is used in the Discussion section to state scientific
“truths” (knowledge expected to be true over time), just as it was in the Results
section. Note that interpretations and/or mechanisms put forth in a Discussion
section are often considered to be “truths” and therefore are stated in presenttense active voice. Table 5.1 summarizes common verb tense–voice combinations
and their functions, with example sentences.
Exercise 5.14
Examine sentences 1–6 below (adapted from Wu et al., 2004). Using table 4.1,
table 5.1, and the information presented in this chapter, do the following:
a. Determine the function(s) of each sentence.
b. Identify the tense–voice combination(s) used in each sentence.
c. Decide whether the tense–voice combinations are appropriate, given the
function(s) of the sentence. Rewrite the sentence, if necessary, so that it is
more appropriate for a Discussion section.
1. Because fruits and vegetables are the major antioxidant sources in the
daily diet of humans, we calculated estimated daily antioxidant capacity
intake from these foods.
2. Our data suggested that foods with active polyphenolic flavonoids were
more resistant than foods with vitamins and related compounds.
3. Removal of the peel is one factor that influences antioxidant capacity (28, 66)
as indicated by lower values in apples compared to that of the intact apple.
Writing the Discussion Section
187
4. In our study, cooked tomatoes have a significantly higher H-ORACFL and
L-ORACFL compared to uncooked samples, which agrees with observations in previous studies (42, 68).
5. Under normal reaction conditions, phenolic compounds are the predominant antioxidants in hydrophilic extracts of samples that easily transfer
one hydrogen to the peroxy radical (ROO·).
6. In summary, the lipophilic and hydrophilic ORACFL values for more than
100 common foods in U.S. markets are obtained for the first time.
Use of “We”
The word we (used to refer to the authors of the work) is commonly used to
achieve the following purposes in the Discussion section:
To indicate a decision or course of action
P6 To correct this fluctuation, we incorporated caffeine standard
measurements. (Yan et al., 2007)
P7 To further validate the suitability of using caffeine as a standard, we
tested 15 additional compounds. (Adapted from Yan et al., 2007)
To compare findings with previous works
P8 However, like others,28 we often observed quantification inconsistencies
when compounds with adjacent nitrogen atoms were analyzed. (Adapted
from Yan et al., 2007)
P9 Previously, we reported that oral intake of BCAs has many beneficial
physiological effects (2–6). (From Matsumoto et al., 2006)
To offer an interpretation
P10 We speculate that, due to structural variations, some unavoidable signal
loss may be structure dependent and an error range of 10–20% is
possible. (Yan et al., 2007)
P11 Therefore, we assumed the decrease of mitochondrial membrane
potential and release of cytochrome c to cytosol did not happen in the
PDTC-pretreated cells. (Cheng et al., 2006)
To report or summarize findings
P12 We found that sulfite alters the pattern of expression of the main
aldehyde dehydrogenase gene, reinforcing the link at the molecular
level between both metabolites. (Adapted from Aranda et al., 2006)
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Table 5.1 Common functions of different verb tense–voice combinations in Discussion sections.
Function
Tense–Voice
Combination
Example
To remind readers about
what was studied in the
current work
Past (active or
passive)
In this work, three Cr3+ compounds were
examined for their impact on genotoxicity and cell
proliferation in vitro (From Plaper et al., 2002)
(past–passive)
To remind readers about/
summarize specific result(s)
in the current work
Past (active or
passive)
Similar to regular garlic, regular broccoli florets
reduced the incidence of mammary tumors (From
Finley et al., 2001) (past–active)
To share corroborating or
conflicting results from
others’ works
Past (active or
passive)
Uptake of dissolved organic carbon by zebra
mussels was also reported by Roditi et al. (30).
(Adapted from Voets et al., 2004) (past–passive)
To interpret results
presented in the current
work
Present–active
The 0.5 TU threshold is arbitrary but suggests
a strong likelihood that the analyte makes a
substantial contribution to the observed mortality.
(From Weston et al., 2004)
To propose “truths” based
on the current work and
others’ works
Present–active
The data in this paper are consistent with a wealth
of evidence showing that dietary Se consumed in
excess of the Recommended Dietary Allowance
lowers the risk of several important cancers (2, 13,
26, 27). (From Finley et al., 2001)
To present the take-home
message of the current
work
Present–active
In summary, (R)-phenylglycine amide 1 is an
excellent chiral auxiliary in the asymmetric
Strecker reaction with pivaldehyde or
3,4-dimethoxyphenyl-acetone. (From Boesten
et al., 2001)
To suggest overall
implications and/or
applications of the current
work
Present–active
The good sensitivity, excellent selectivity, and
simplicity of use of the DNA biosensor make it
more compatible for integrating with on-chip
PCR reactors than other DNA biosensors of
which we are aware. (Adapted from Wong and
Gooding, 2006)
P13 In conclusion, we have demonstrated that PDTC inhibits
luteolin-induced apoptosis, which it might do by causing the
phosphorylation of caspase-9 in human leukemia HL-60 cells.
(Cheng et al., 2006)
Writing the Discussion Section
189
Exercise 5.15
Consider the sentences below, all taken from Discussion sections. What are the
authors trying to achieve in each sentence: (1) indicate a decision or course of
action, (2) compare findings with previous works, (3) offer an interpretation, or
(4) report or summarize findings?
a. We used this value as a correction factor for caffeine calibration, and all compound analyses were adjusted accordingly. (Adapted from Yan et al., 2007)
b. We rationalize that this is likely the root cause for the structure dependence.
(From Yan et al., 2007)
c. In conclusion, we have shown that PM2.5 contains stable radicals that can be
detected by EPR. (From Dellinger et al., 2001)
d. In our previous study, we observed that luteolin could trigger cytochrome c
released to cytosol. (Cheng et al., 2006)
e. We confirmed that, when compounds contain isolated nitrogen atoms, the
response is close to quantitative with a variation about 10–20% depending
on structures. (Adapted from Yan et al., 2007)
Hedging Words
Hedging is the mark of a professional scientist, one who acknowledges the
caution with which he or she does science and writes on science.
—Crismore and Farnsworth (1990)
As mentioned at the beginning of the chapter, the language of a Discussion section is typified by restraint and understatement. The goal is to let the science
speak for itself. Words should be used to clarify, not convince. By overselling a
point, even one that is well substantiated, you will appear to be biased. For this
reason, chemists soften their interpretations and claims to “truth” by using hedging words. The bar below lists verbs that are commonly used in combination with
hedging words, such as can, may, and might.
Verbs Used with Hedging Words
The hedging words can, could, may, might, should, and would commonly occur with verbs
such as these:
190
assign
conclude
expect
make
rationalize
attribute
deduce
explain
observe
relate
cause
determine
form
obtain
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Exercise 5.16
Consider the passages below. Find words that indicate that the authors are hedging, rather than offering proof. Then read over excerpts 5A–5E to identify at least
five additional examples of hedging.
a. Our results suggest that Cr3+ has an impact on DNA, DNA topology, and
consequently processes leading to cell growth and proliferation. This could
ultimately lead to the mutagenic and carcinogenic potential of Cr3+. Because
it is known that humans exposed to different Cr3+ species accumulate high
levels of Cr3+ intracellularly (17), presented results may have an impact on
human intake of Cr3+ as a nutrition additive. (Passage P5)
b. A possible explanation for this effect can be attributed to an increased
density and viscosity of the milk–NaOH phase when NaOH concentration
increases. (Excerpt 5A)
c. In all cases, this factor has a positive effect and it appears to be of increasing
importance as the degree of chlorination of the PCBs increases. (Excerpt 5A)
d. For the highly chlorinated PCBs, the two fibers tested seem to have similar
performance, and this factor lacks statistical significance. (Excerpt 5A)
e. The results presented here suggest a new mechanism of toxicity for PM 2.5
based on sustained hydroxyl radical generation by the semiquinone radicals present in PM2.5. Because a substantial fraction of the fine particles in
the atmosphere arise from combustion sources (9), it is possible that the
deleterious health effects associated with PM2.5 can be at least partially
ascribed to radicals associated with combustion-generated particulate matter.
(Excerpt 5C)
f. By using zinc salts as catalysts, we showed that water can be used as the solvent despite the relative insolubility of the starting materials. This discovery
should facilitate the preparation of tetrazoles in the laboratory. (Excerpt 5D)
Exercise 5.17
All hedges have been removed from the paragraph below (adapted from Lissens
et al., 2004). Rewrite this paragraph so that it better conforms to the conventions
of a journal article. Remember that not all sentences may require hedging. (Note
that when you add hedging words, you may have to make other minor changes
in the sentence.)
Effects of WO on Anaerobic Biodegradability of Raw Waste. Figure 1 shows the
effect of the composition of a waste stream (Figure 1A) as well as the effect of the applied
wet oxidation conditions (Figure 1B) on the anaerobic biodegradability of raw and
digested waste after assessing wet oxidation. Although a doubling of the methane yield
was achieved for wet oxidation yard waste compared to the reference, a minor increase
Writing the Discussion Section
191
(7%) in methane yield was observed when raw food waste was subjected to wet oxidation. This was due to inherent differences in lignocellulose composition and characteristics of the lignin fraction of both wastes. Although it was previously shown that both
wastes have a similar lignin content (21–22 g/100 g) and also rather similar cellulose and
hemicellulose content (Table 2) (18, 19), the amount of readily biodegradable and soluble
organics in the food waste must be much higher than that in the woody yard waste.
Hence, the wet oxidation pretreatment leads to a substantial beneficial effect on the biodegradability of the fibrous yard waste, although this was not the case for food waste.
5D Writing on Your Own: Practice Peer Review
Imagine that a colleague has asked you to review a draft of a Discussion section. Based
on what you have learned in this chapter, read the draft, background information, and
instructions at the end of this chapter under “Peer Review Practice: Discussion Section” and
provide written feedback.
5E Writing on Your Own: Fine-Tune Your Discussion Section
By now, you should have made good progress writing your own Discussion section; thus,
it is time to refine and edit your work. Focus on each of the areas specified below. Refer to
chapter 18 to guide you in the revision process.
1. Organization of text: Check your overall organizational structure. Did you follow the
move structure outlined in figure 5.1 and include appropriate subheadings?
2. Audience and conciseness: Are you writing for an expert audience, leaving out unnecessary details? Try to find at least three sentences that can be written more clearly and
concisely. Have you directed your closing comments (e.g., applications and/or implications) to a more scientific audience? Check that you used we and hedging words
appropriately.
3. Writing conventions: Check to be sure that you have used voice and tense correctly.
4. Grammar and mechanics: Check for typos and errors in spelling, subject–verb agreement, and punctuation. Be sure you have used troublesome words such as effect, affect,
and data correctly.
5. Scientific content: Have you correctly conveyed the science in your work? Have you
used words and units correctly? If asked, could you define all of the words you have
used in this section? Do you understand the implications of your work?
After thoroughly reviewing your own Discussion section, ask a colleague to review your
work. A “new set of eyes” will pick up mistakes that you can no longer see because you are
too familiar with your own writing. To facilitate this process, use the Peer Review Memo
on the Write Like a Chemist Web site. After your paper has been reviewed (and you have
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reviewed another’s paper), use the feedback provided to make final changes to your
Discussion section.
Finalizing Your Written Work
See chapter 18.
Chapter Review
As a self-assessment of what you’ve learned in this chapter, define each of the following terms for a friend or colleague who is new to the field:
hand-waving argument
hedging
hyphenated modifier
implications
interpretation
scheme
take-home message
Also, explain the following to a friend or colleague who has not yet given much
thought to writing a journal article Discussion section:
■
Main purpose(s) of a Discussion section
■
Standard moves of a Discussion section
■
Use of present-tense active voice in a Discussion section
■
Use of we in a Discussion section
■
Purpose(s) of hedging and common hedges
Additional Exercises
Exercise 5.18
Revise the following sentences (intended for a Discussion section) to make them
more concise:
a. It is likely that both specific and nonspecific effects add up to lead to the
production of the observed differences in CO stretching frequencies.
b. In the case of the photobleaching experiment, the analysis is relatively
straightforward, and it is further simplified by the molecular symmetry of 1.
Writing the Discussion Section
193
c. Conversion trends a lot like those shown in Figure 12 have been reported in
an article by Al-Dhabi et al.3
Exercise 5.19
Excerpt 5F includes the Discussion section from a 2001 article in the Journal of
Agricultural and Food Chemistry. Read the excerpt and then complete the following
tasks:
a. Identify each of the moves and submoves of the Discussion section. Does this
Discussion section follow the typical move structure presented in figure 5.1,
or does it vary somewhat? If it varies, explain the deviation.
b. Find instances of hedging in the excerpt. What purposes do these examples
of hedging serve?
c. Do the authors of this Discussion section both interpret results and apply
them to a wider context? Do the authors explore the broader implications of
their work? If so, what applications are mentioned? What implications are
mentioned?
d. Does this excerpt include any two-word modifiers? If so, list them and determine if they are hyphenated properly.
e. Consider the authors’ use of verb tense and voice. Find at least two sentences
in which present-tense active voice is used to state interpretations.
Excerpt 5F (from Finley et al., 2001)
Discussion
The data in this paper are consistent with a wealth of evidence showing that dietary
Se consumed in excess of the Recommended Dietary Allowance lowers the risk of several important cancers (2, 14, 26, 27). Previous research has established a strong association between the dietary form of Se and the cancer-preventive properties of this element
(5, 28). This paper extends the evidence that Se in chemical forms known to accumulate
in garlic and some Brassica species is especially effective in the prevention of chemically
induced carcinogenesis (14, 17).
Similar to regular garlic, regular broccoli florets reduced the incidence of mammary
tumors (Table 1) (3); this indicates that there are components in addition to Se in each
of these plants that have anticarcinogenic activity. Se-enriched broccoli was not more
effective (Table 1) than enriched garlic (3) in reducing the number of tumors; this suggests that the combination of sulforaphane, indole carbinol, and chlorophyll with Se did
not provide additional protection against mammary tumors. However, firm conclusions
cannot be made because the concentrations of these compounds were not determined in
the broccoli used in this experiment and because a direct comparison of high-Se garlic
and high-Se broccoli was not made.
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Results of the second experiment (Table 3) show that Se-enriched broccoli sprouts
have properties similar to enriched broccoli florets that contain SeMSC as the predominant form of Se (13). Consumption of Se from high-Se broccoli sprouts, as compared
to Se from selenite, resulted in a significant decrease in the number of aberrant crypts.
Additional experimentation is needed to determine whether the decrease in carcinogenesis is a result primarily of the presence of SeMSC, and if there is a correlation between
SeMSC content in enriched plants and the reduction of carcinogenesis. If such a correlation is established, then the SeMSC content of various enriched plants could be used to
screen for the greatest efficacy in tumor reduction. Se-enriched broccoli appears to be
similar to enriched broccoli florets, for which the predominant form of selenium was
also shown to be SeMSC (13).
High-Se broccoli sprouts were not more effective than high-Se broccoli florets for the
prevention of DMH-induced aberrant colon crypts (Table 3). This result, in conjunction with the fi nding that low-Se broccoli was not more effective than regular garlic for
prevention of MNU-induced mammary tumors (experiment 1, Table 1), provides strong
evidence that the cancer-preventive qualities of secondary plant compounds found
in broccoli but not garlic, such as sulforaphane, indole carbinol, and chlorophyll, are
masked by a much stronger protective effect of Se in broccoli.
The present results also point to differences between the mammary tumor model and
the ACF model for evaluating the potential cancer protective effects of Se in broccoli. A
previous study (17) showed that high-Se broccoli florets decreased the number of DMHinduced ACF. Similarly, in the present study high-Se broccoli sprouts decreased DMHinduced ACF, but low-Se broccoli sprouts alone did not have any effect (Table 3). In the
mammary tumor model, however, broccoli alone, similar to garlic alone (3), reduced the
number of tumors (Table 1). This contrasting effect could be the result of a difference
between tumor and preneoplastic lesion models, a difference between carcinogens, or a
difference between mammary and colonic tissues.
In response to the fi ndings of the Se-responsive reduction of cancer risk in
humans, many nutritionists and other health professionals have begun to suggest
supplemental intakes of as much as 200 µg of Se/day. However, the present results
provide evidence that the total Se intake is not the only factor to consider for the
reduction of carcinogenesis. Similar to our previous fi ndings concerning the ability
of high-Se broccoli to reduce the incidence of colon cancer (17), an equal amount of
Se supplied as selenite did not significantly reduce the incidence of ACF. This means
that in addition to total Se intake, the form of Se in a particular food or supplement must be taken into consideration. Grains and meat supply a major portion of
dietary Se (29), and the Se in grains and meat is very effective for increasing tissue Se
concentrations and GSH-Px activities (30–32). However, the form of Se in meat and
grain is greatly different from the form in broccoli and garlic (13), foods that seem to
provide superior anticarcinogenic properties. Consequently, more work needs to be
conducted before concrete recommendations of the optimum forms of supplemental
Se can be made.
Writing the Discussion Section
195
Exercise 5.20
Excerpt 5G showcases the last move of a Discussion section.
a. As you read the excerpt, identify the goals of the work, the methodology
used, the major findings, and the interpretation of findings.
b. In your opinion, is this a typical conclusion for a Discussion section? Why or
why not?
Excerpt 5G (adapted from Yu et al., 2001)
In summary, we have designed and synthesized a new ferrocene-modified phosphoramidite 9 for the electronic detection of single-base mismatches in an array format.
By employing automated DNA/RNA synthesis techniques the ferrocenyl complexes
have been inserted into oligonucleotides at various positions. The thermal stability of
the metal-containing DNA oligonucleotides has been investigated and indicates that
the incorporation of 9 into DNA oligonucleotides causes little or no destabilization of
the duplex. Electrochemical analysis of oligonucleotides containing 9 reveals that the
derivative can function as a signaling probe for the electronic detection of nucleic acids.
When incorporated into a CMS-DNA chip, results clearly show that dual-signaling
oligonucleotide probes containing 9 and the phosphoramidite 1 detect single-base
mismatches.
Exercise 5.21
Reflect on what you have learned about writing a Discussion section for a journal
article. Select one of the reflection questions below and write a thoughtful and
thorough response:
a. Reflect on the move structure of a typical Discussion section.
■
■
■
How does knowing the typical move structure of a Discussion section
assist you with reading authentic excerpts from the chemical literature?
How has knowing the typical move structure of a Discussion section
helped you write your own Discussion section?
Which parts of the typical move structure of a Discussion section are easiest to write? Most difficult to write? Why?
b. Reflect on the different ways in which authors connect their Results and
Discussion sections (i.e., stand-alone Discussion, blocked R&D, iterative
R&D, integrated R&D).
■
■
■
Which format has the greatest appeal to you? Why?
Which format is the easiest to read? The most difficult to read? Why?
Can you explain the logic of each formatting convention? What might the
benefits of each format be?
c. Reflect on your experience writing your own Discussion section.
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■
■
■
What problems did you encounter writing your Discussion section? How
did you resolve your problems?
What parts of this chapter have helped you the most in writing your
Discussion? How did you use chapter information to assist you in your
writing?
What have you learned from the experience of writing your Discussion
that will help you in the future?
Peer Review Practice: Discussion Section
Imagine that a classmate has asked you to review and provide feedback on a draft
of a Discussion section. Your valuable feedback will be used to improve the written work.
Using parts 2 and 3 of the Peer Review Memo on the Write Like a Chemist Web
site, review the Discussion section below. We have included the last paragraph
from the Introduction section to help you better understand the Discussion. You
do not need to review the Introduction. Provide specific suggestions that your
classmate can use to improve the Discussion section. (The Discussion section
below is adapted from an original source, noted in the Instructor’s Answer Key.)
[Excerpt from the Introduction]
The aim of this study was to investigate the effect of high but environmentally realistic concentrations of humic acid on the relative long-term accumulation of Cd in the
freshwater mussel D. polymorpha under controlled laboratory conditions. We assessed
whether the long-term uptake of Cd is in agreement with the free-ion activity model and
if Cd accumulation is related to the Cd 2+-ion activity in the water.
Discussion
1
As stated previously in the Methods section, zebra mussels were exposed to varying
2 concentrations of cadmium in 80 L of water for 31 days. Each aquarium contained 150
3 individuals at the start of the experiment. Five experimental aquaria and one control
4 aquarium were run. We found that zebra mussels efficiently accumulate cadmium and
5 other heavy metals. Even at low environmental Cd concentrations or short exposure
6 periods cadmium concentrations in the tissues are significantly elevated. Our data
7 shows that the cadmium concentration in zebra mussel tissue increases from 0.054 ±
8 0.004 to 0.214 ± 0.031 μmol/g dry wt at an exposure concentration of 0.020 μM after
9 31 days. The uptake rate of cadmium is strongly correlated with the free Cd-ion activi10 ties in the water, and the Cd concentrations in the tissues are still increasing at the end
11 of the 31-day exposure period.
12
The presence of humic acid decreases the cadmium accumulation by the zebra mus13 sels. Although this reduced accumulation can mainly be explained by the decrease in
Writing the Discussion Section
197
14 free cadmium-ion activity in the exposure water, cadmium accumulation was higher
15 than expected based on cadmium-ion activity alone. This proves that zebra mussels
16 must accumulate cadmium complexed to humic acid. The Cd2+ binding to humic acid
17 must occur through interactions between the cadmium ion and negatively charged sur18 face functional groups.
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6
Writing the Introduction Section
In writing an article about my chemical research, I like to use as a model
a travel or travel-adventure article that might appear in a magazine
or in the travel section of a newspaper. Because, after all, what is
research but a voyage to a completely unknown place where everything
is new. So the first few paragraphs of the article [the Introduction]
should tell the potential reader where we are going and why.
—Charles H. DePuy, University of Colorado–Boulder
This chapter focuses on the Introduction, the first formal section of the journal
article. The Introduction is often the first section to be read (by readers) but the
last section to be written (by writers). This is because the Introduction must tell
readers “where the article is going and why”, a mission that is most easily accomplished after the rest of the sections have been completed. By the end of this
chapter, you should be able to do following:
■
Write an Introduction following its conventional organizational structure
■
Compose the all-important opening sentence of an Introduction
■
Cite and summarize others’ works in concise and appropriate ways
■
Conclude your Introduction in an effective manner
As you work through the chapter, you will write an Introduction section for your
own paper. The Writing on Your Own tasks throughout the chapter guide you
step-by step as you do the following:
6A Read and paraphrase the literature
6B Prepare to write
6C Draft your opening paragraph
6D Identify a gap
6E Draft your full Introduction
6F Practice peer review
6G Fine-tune your Introduction
The Introduction, as its name implies, sets the stage for the rest of the journal
article by introducing the research area, describing its importance, and hinting
at what new knowledge and insights the authors have gained. The Introduction
is also where authors summarize others’ works; this involves several important
writing skills such as paraphrasing, writing concisely, and correctly citing the literature. Paraphrasing and writing concisely are addressed in this chapter; citing
the literature is addressed in chapter 17.
Citing the Literature
See chapter 17 for information on how and what to cite from the primary literature.
Reading and Analyzing Writing
At long last, we ask you to read the Introduction to the aldehydes-in-beer article
(excerpt 6A). If you have progressed through these textbook chapters sequentially,
you have already read the Methods, Results, and Discussion sections. Admittedly,
this order may seem a bit unusual. Remember, however, we want you to read
the Introduction through the eyes of the writer, not the reader. As authors write
their Introduction, they already know what unfolds in the rest of their paper;
now you, too, have this perspective. (If necessary, refer back to chapters 3–5,
and excerpts 3A and 4A, to refresh your memory.) As you read the Introduction,
consider how the authors introduce their story of scientific discovery.
Exercise 6.1
As you read through excerpt 6A, complete the following tasks:
a. Identify the major purpose of each paragraph. Use these purposes to propose
a move structure for the Introduction.
b. How detailed are the authors’ descriptions of others’ works?
c. What do you notice about the language and writing conventions used by the
authors?
d. Refer back to excerpts 3A (Methods) and 4A (Results and Discussion). Jot
down two to three key concepts for each excerpt. Where, and to what extent,
is this information shared in the Introduction?
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Excerpt 6A (from Vesely et al., 2003)
Introduction
Carbonyl compounds, particularly aldehydes, are considered to play an important
role in the deterioration of beer flavor and aroma during storage. Strecker degradation of
amino acids, melanoidin-mediated oxidation of higher alcohols, oxidative degradation of
lipids, aldol condensation of short-chain aldehydes, and secondary oxidation of long-chain
unsaturated aldehydes are mechanisms implicated in their formation (1). Their levels in
beer are usually very low, and therefore it has always been a challenge for brewing chemists to develop an analytical method that would enable routine analysis of aldehydes.
Several analytical methods for the determination of aldehydes in beer have been
developed, and good results have been obtained using liquid–liquid extraction (2),
distillation (3), or sorbent extraction (4). However, these methods are rather complicated
and not highly selective.
A simple way to increase the selectivity of extraction techniques is to derivatize the
carbonyl compounds. O-(2,3,4,5,6-Pentafluorobenzyl)hydroxylamine (PFBOA) is commonly used as a derivatization agent in gas chromatography (5). This technique has been
applied to the analysis of carbonyl compounds in water and also in beer (6). Although
these methods provide good reproducibility, they are time-consuming and require use of
solvents, materials for the derivatization, and isolation steps. Martos and Pawliszyn (7)
developed an original extraction technique based on PFBOA on-fiber derivatization of
gaseous formaldehyde followed by gas chromatography with flame ionization detection.
In this work, we adapted a method for the analysis of beer aldehydes using solidphase microextraction (SPME) with on-fiber derivatization. This extraction technique
does not require solvents, consists of a one-step sample preparation procedure, and provides high sensitivity and reproducibility. It enabled a detailed study of aldehyde level
changes during packaged beer storage.
Exercise 6.2
Examine the language in excerpt 6A as you answer these questions:
a. Both present and past tenses are used. Find two examples of each. Based on
this Introduction, what general trends might you suggest about the use of
tense in the Introduction of a journal article?
b. Both active voice and passive voice are used. Find two examples of each.
Which voice appears to be used more often?
Exercise 6.3
A central purpose of the Introduction is to help readers understand why the
targeted area of research is important. Reread the first and last paragraphs of
excerpt 6A and then restate the importance of the work in your own words.
Writing the Introduction Section
201
Exercise 6.4
Examine the ways in which the authors of excerpt 6A cite others’ works. Propose
two citation rules that the authors appear to be following.
6A Writing on Your Own: Read and Paraphrase the Literature
In chapters 3–5, we suggested that you begin Writing on Your Own by reviewing the
targeted section (i.e., Methods, Results, and Discussion) in each of the articles that you
collected during your literature search. To prepare to write the Introduction, however, we
recommend that you review each article in its entirety, in order to summarize the major
findings of each work.
Take careful notes as you review each article, looking for key ideas and themes that
will help you organize your notes into categories. Use your own words while taking notes;
avoid the temptation to copy exact words from original sources. In this way, others’ ideas
will be easier to paraphrase when you write your Introduction. Consider these note-taking
guidelines for paraphrasing the works of others:
1. Carefully read the passage that you wish to paraphrase, making sure that you understand what you have read. (This often requires consulting textbooks, reference materials, and other publications cited in the article.)
2. Without looking at the original passage, jot down notes about the passage; try to capture the ideas most relevant to your study.
3. Summarize your notes into a concise, well-worded statement, without looking back at
the original. (Note cards are ideal for this step.)
4. Check your summary against the original to ensure that you have not plagiarized but
have still captured the ideas most relevant to your study.
5. Add full bibliographical information to the summary. The names of all authors, article title,
journal name, volume number, year, and pages (first and last) may eventually be required.
6. Label your summary with a keyword, creating a master list of keywords as you review
the literature. Use these keywords to organize your summaries into categories.
7. Repeat these steps for additional passages in the same article or new passages in other
articles.
Analyzing Audience and Purpose
You have probably noticed that the Introduction is one of the most easily understood sections of a journal article. This is because the Introduction is written for
a more general audience than the rest of the paper. A wide range of readers, from
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students to experts, should be able to read at least parts of the Introduction. The
purposes of the Introduction are also more general than other sections of the
paper:
■
To introduce the area of research
■
To explain the importance of the research area
■
To highlight relevant, precedent works
■
To justify the need for the current work
■
To introduce the current work
The Introduction begins with the most general information (the research area)
and gradually shifts to a more specific focus (the current work), preparing the
reader for the highly specific focus of the Methods section. This transition from
general to specific is apparent in the now-familiar hourglass shape of the journal
article.
Exercise 6.5
Each of the following passages is about a Grignard reaction. Four are from journal
articles (two from Introduction sections and two from Discussion sections), and
one is from a textbook. Based on your understanding of the purpose and intended
audience of each section and genre, read each passage and decide where it comes
from. Explain what information you used to make your decisions.
a. Entirely different regioselectivity to that observed with the BuMgX/CuCN
reagents was obtained with Bu2Cu(CN)Li2 in THF1 and BuLi/CuCN (cat.) in
both THF and Et2O . . . , while other combinations of the reagents and the
solvent showed a similar efficiency. (Adapted from Ito et al., 2001)
b. The Grignard reagent has probably been the most widely used intermediate in organic chemistry since its introduction by Victor Grignard in 1900.1
Despite this wide use, it is not possible to assign a specific structure for a
particular reagent. This is because both RMgX and R 2Mg are formed during
preparation of the reagent and are connected by the equilibrium described by
Schlenk and Schlenk.2 (Adapted from Walter, 2000)
c. Organohalides (RX) react with magnesium metal in ether or tetrahydrofuran
(THF) solvent to yield organomagnesium halides, RMgX. The products,
called Grignard reagents after their discoverer, Victor Grignard, are examples
of organometallic compounds because they contain a carbon–metal bond.
(Adapted from McMurry, 2004)
d. The mechanism of the Grignard reaction with chlorosilanes is different from
that with alkoxysilanes. An SEi mechanism, common for electrophilic substitution reaction with organometallic compounds,1–3 can be assumed. (Adapted
from Tuulmets et al., 2003)
Writing the Introduction Section
203
e. One of the most important methods for forming carbon–carbon bonds is
through the nucleophilic addition of an organometallic reagent to a carbonyl derivative. Such reactions are exemplified by the Barbier-Grignard type
reactions.1–3 (Adapted from Li and Meng, 2000)
Analyzing Organization
The Introduction, like other sections of a journal article, follows a conventional set
of moves. In fact, the move structure for the Introduction section is likely the most
consistently followed move structure presented in this textbook (figure 6.1).
The first move, with three submoves, has the broad purpose of describing
the general research area. Submove 1.1 identifies the research topic, and submove 1.2 stresses its importance. Together, these two submoves are frequently
accomplished in the first few sentences of the paper. Note that only the general
topic is mentioned at this point, not the specific work that is presented in the
paper. (We refer to the specific work presented in the paper as the current work.)
Submove 1.3 is where authors summarize essential works in the field and situate the current work in its appropriate context. This submove does not provide
an exhaustive review of the literature but rather includes “sound bites” that alert
readers to works that critically influenced the current work or led to fundamental
knowledge in the field. The entire first move is usually accomplished in a few
1. Introduce the Research Area
1.1 Identify the research area
1.2 Establish the importance of the research area
1.3 Provide essential background information
about the research area
General
Cite
relevant
literature
2. Identify a Gap (or Gaps)
3. Fill the Gap
3.1 Introduce the current work
3.2 Preview key findings of the current work
(optional)
Specific
Figure 6.1 A visual representation of the move structure for a typical Introduction section.
204
The Journal Article
paragraphs, with most attention devoted to submove 1.3. All three submoves are
strengthened by citations to the literature. Works by other authors are cited as
well as previous, relevant works by the current authors.
Current Work
This term is reserved for the specific work presented in the journal article. The phrase
should not be used to refer to others’ works or even past works by the authors.
With a few exceptions, most Introduction sections refrain from mentioning the current
work in the first move.
See table 6.3 for other phrases used to refer to the current work.
The second move in the Introduction section (Identify a Gap) shifts the reader’s attention from what has been done (or learned or understood) to what still
needs to be done (or learned or understood). The essence of this move is captured
in the sentence, “Although much is known about X, little is known about Y.” Gap
statements come in various forms; a few possibilities are listed in table 6.1. Of
course, to correctly identify a gap, the authors must have thoroughly reviewed the
literature; hence, citations to the literature are common in this move, too.
After a gap has been identified, the third and final move of the Introduction section is to fill the gap. This move typically comprises a short paragraph at the end
of the Introduction and begins with a phrase like “In this paper, we. . . . ” At last,
Table 6.1 Examples of gap statements. (X represents what has been done, learned, or
understood; Y represents what needs to be done, learned, or understood.)
Type
Example
A question that remains unanswered
Numerous questions remain unanswered
about Y.
A research area that remains poorly
understood
Although much has been learned about X, Y
remains poorly understood.
A next step that needs to be taken
The next step is to apply X to the study of Y.
An area that has yet to be studied
X has been the subject of several studies;
however, to our knowledge, no studies on Y
have been reported.
A procedure that needs to be improved
(made less expensive, simpler, more
efficient, etc.)
Although X achieves the desired detection
limits, the method is costly and timeconsuming.
A new hypothesis or observation that
needs to be validated
Additional studies are needed to corroborate
these findings.
Writing the Introduction Section
205
the authors can refer to the current work, and many use the personal pronoun we
to accomplish this task. The authors give a short description of the current work
(typically a few sentences), highlighting how the work fills the identified gap (submove 3.1). The Introduction can end here, or the authors can elect to preview their
principal findings (submove 3.2). If the authors do the latter, care must be taken
not to repeat sentences verbatim that appear elsewhere in the paper.
Exercise 6.6
Reread excerpt 6A with the move structure of the Introduction section in mind.
Which moves are present? Which sentences are associated with which moves?
Support your answers with specific examples from the text.
As you might suspect, not all authors or journals adhere strictly to the move structure
depicted in figure 6.1. One variation (employed commonly by organic chemists) is
to mention the gap and the current work in the first paragraph of the Introduction.
We will encounter one such variation later in this chapter, when we examine the
Introduction section of a journal article from The Journal of Organic Chemistry.
6B Writing on Your Own: Prepare to Write
With knowledge of the move structure for the Introduction section in mind, look through
your notes and be sure that you have sufficient information to address each move. How
will you introduce your topic? How will you justify the importance of your research area?
What essential works will you describe to provide relevant background information? What
gap does your current work fill? If you cannot address each of these questions, you may
need to extend your review of the literature.
Analyzing Excerpts
If a chemical article is going to describe something new about a wellknown reaction, the introduction might say, “Although the study of
substitution reactions occupies a large portion of undergraduate
chemistry and has been extensively studied for decades, no one has
examined how the reactions change when the reagents are in the gas
phase instead of in solution.”
—Charles H. DePuy, University of Colorado–Boulder
We now read and analyze excerpts of Introduction sections, including those from
articles examined in chapters 3–5. In part 1, we examine the excerpts one move
206
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at a time; in part 2, we look specifically at ways to make your writing more concise and fluid in the Introduction.
Part 1: Analyzing Writing Move by Move
Move 1: Introduce the Research Area
As revealed in figure 6.1, the research area is introduced in three submoves. In
the first submove, the research area is described broadly. This step is initiated
and often accomplished in the opening sentence of the paper. This all-important
first sentence, in many genres, is used to set the tone for the work (see figure 6.2);
however, in chemistry journal articles, the first sentence tells the reader, with a
broad stroke, what the story is about. Consider the following examples, in which
the general topic is mentioned at the start of each sentence (our bolding):
P1 Chromium is a metal widely distributed in soil and plants (1). (From
Plaper et al., 2002)
P2 Polychlorinated biphenyls (PCBs) are a group of pollutants widely
distributed in the environment due to their generous use in the past,
Figure 6.2 Even Snoopy recognizes the importance of the opening sentence. In a novel, the fi rst
sentence sets the tone; in a journal article, it identifies the topic. PEANUTS: ©United Feature
Syndicate, Inc.
Writing the Introduction Section
207
their lipophilic character, and their chemical stability.1,2 (From Llompart
et al., 2001)
The specific content of each article (Cr3+ toxicity and the detection of PCBs in fullfat milk, respectively) is stated much later in the Introduction section. Four other
examples of opening sentences are included in exercise 6.7.
All-Important Opening Sentence
The first sentence in the Introduction section should convey the general topic of the paper
(i.e., the research area), not the specific work to be reported.
Exercise 6.7
Passages P3–P6 open the Introduction sections to four key articles cited throughout the textbook. Briefly state the general topic of each article based on only the
first sentence.
P3 Since the possibility of using cyclodextrins (CDs) for soil
remediation was first mentioned in 1992 (1), two main soil treatment
technologies have been developed: washing of contaminated soils
with a relatively concentrated CD solution (sugar flushing) (2) and
using small amounts of CDs as a bioavailability-enhancing additive to
accelerate the biodegradation of organic pollutants (3). (From Jozefaciuk
et al., 2003)
P4 Epidemiological studies indicate increases in human mortality and
morbidity due to exposure to airborne fine particulate matter (1). (From
Dellinger et al., 2001)
P5 The asymmetric synthesis of α-amino acids and derivatives is an
important topic as a result of their extensive use in pharmaceuticals and
agrochemicals and as chiral ligands. (From Boesten et al., 2001)
P6 The literature on tetrazoles is expanding rapidly.1 (From Demko and
Sharpless, 2001)
Since vs. Because
See appendix A for more information on these easily confused words.
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Exercise 6.8
Select a chemistry journal, and jot down its title. Select five research articles
from the journal, and read the first sentence of each article. Based only on the
first sentence, identify the general topic of each paper. Summarize the topic in
a word or two. Repeat this exercise for a second journal. Did you run across
any articles in which the general topic is not identified in the first sentence?
Explain.
Two writing features are worth pointing out regarding the opening sentence of a
journal article. First, the topic is usually introduced in the present tense; only one
passage above (P3) did not use present tense. Second, citations to the literature
are quite common in the first sentence. Once again, all passages but one (P5)
included at least one citation in the first sentence.
Equally important is what not to do in the opening sentence. First, we caution against using catchy language. Unlike many forms of writing (e.g., Snoopy’s
novel in figure 6.2), when writing for expert chemists, catchy language must be
avoided, not only in the opening sentence but throughout the work. Consider the
following two sets of opening sentences; the first is written for a general audience
and the second for an expert audience:
Written for a general audience Beer foam. Most beer drinkers try
to minimize it when doing a pour.
(McCue, 2002)
Written for an expert audience Foam and flavor stability are important
considerations for a brewer as it is
through these that the consumer judges
the quality of the beer. However, these
foaming and flavor properties are
seriously damaged by lipids . . . (Cooper et al.,
2002)
Second, we caution against mentioning the current work in the opening sentence.
As stated above, the conventional place to mention the current work is toward
the end of the Introduction section. Third, it is uncommon to mention scientists
by name in the opening sentence. Although the opening sentence often includes
citations to the literature, names are normally not included.
Exercise 6.9
The following sentences appear in the Introduction section of an article on asbestos (Webber et al., 2004). Based on content and language, which is likely the first
Writing the Introduction Section
209
sentence of the Introduction? Based on the move structure in figure 6.1, predict
the order of all three sentences:
a. This paper demonstrates the first reconstruction of airborne asbestos concentrations from the last century, including the periods of highest exposures.
b. Asbestos fibers are naturally occurring hydrated silicate mineral fibers that
have found myriad uses in the 20th century.
c. However, airborne asbestos fibers became the well-recognized cause of asbestosis, bronchogenic carcinoma, and mesothelioma during the latter half of
that century (1–3).
Exercise 6.10
Rewrite the following sentences so that they conform more closely to the conventions of an opening sentence for the Introduction section of a journal article:
a. We used NMR spectroscopy to show that we had successfully synthesized a
novel arylated quinoline, a molecule belonging to a class known to be important in biologically active compounds.1–3
b. Smith et al.1 reviewed carbon nanotubes (CNTs) in their recent publications
and showed that CNTs have novel electrical properties1–3 and many possible
applications in electronic and sensing devices.2,4
c. Believe it or not, with the wonders of modern science, we can now manipulate single biomolecules such as DNA and proteins, and by using highly
focused laser light, we can grab them and move them to new positions in
new orientations.
d. You already know that tobacco causes cancer, but did you know that it’s the
nitrosamines in the tobacco that lead to carcinogenesis?
After the general topic has been identified in the Introduction section, the next
step is to describe the importance of the research area (submove 1.2). The authors
must explain why the subject is important and refer to key articles in the permanent literature to substantiate this importance. Many authors begin to establish
the importance of the research area in the very first sentence, along with identifying the topic of the paper. Thus, for example, in P4 (exercise 6.7), we learn both
that fine particulate matter (PM) is the topic of the article and that studying PM
is important because exposure can lead to human mortality and morbidity. The
authors go on to stress this importance even more strongly in the rest of the first
full paragraph of the article:
P7 Epidemiological studies indicate increases in human mortality and
morbidity due to exposure to airborne fine particulate matter (1). This
has led to the promulgation of stringent new air pollution regulations
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that limit the atmospheric concentration of particles with a mean
aerodynamic diameter of less than 2.5 µm, PM2.5. The link between
exposure of PM2.5 and excess mortality is well established (1, 3, 4),
although the causative agent(s) have not been conclusively identified,
and the confounding of effects due to co-exposure to gaseous pollutants
is inherently difficult to analyze (5, 6). The principal source of airborne
PM2.5 is combustion emissions, either primary particulate emissions
or particulate matter formed from atmospheric reactions of gaseous
combustion emission (7–9). Thus, it is likely that species directly emitted
from combustion sources or their atmospheric reaction products play
a role in the health effects of airborne PM2.5. (Adapted from Dellinger
et al., 2001)
Principal vs. Principle
See appendix A for more information on these easily confused words.
Impact on human health is a common theme used by authors to justify the importance of their research. This theme also appears in the Introduction section of
the chromium article. As illustrated in P8, the authors first highlight the welldocumented health risks of hexavalent chromium (Cr6+) and then indicate why it
is also important to study trivalent chromium (Cr3+).
P8 In numerous studies, Cr6+ compounds have been shown to be
carcinogenic in vivo and mutagenic in vitro. Cr6+ can induce tumors in
experimental animals and can neoplastically transform cells in culture
(2). In cultured cells, Cr6+ induces DNA single-strand breaks, binding of
amino acids and proteins to DNA, DNA–DNA cross-links, and Cr–DNA
adducts (2, 4–8). . . . In contrast to Cr6+, trivalent chromium (Cr3+) is
actually an essential nutrient, needed for the expression of glucose
tolerance (1). Because the normal human dietary intake of this element
is less than 60% of the minimum suggested intake (1), many people,
particularly in developed countries, supplement their diets with trivalent
chromium. The use of chromium nutrition additives is widespread and
unsupervised, and there is no awareness of possible side effects. It is
therefore important that Cr3+ toxicity be investigated in further detail, to
ensure safer application of this additive. (Adapted from Plaper et al., 2002)
Farther vs. Further
See appendix A for more information on these easily confused words.
Writing the Introduction Section
211
Another common theme that authors use to establish importance involves environmental impacts. For example, an environmental slant is used in the first
sentence of the cyclodextrin article (P3, exercise 6.7), where the study of cyclodextrins is justified based on their role in soil remediation. The importance of
work that benefits air or water quality and/or promotes green chemistry can
also be stressed. Work is also viewed as important if it has cross-disciplinary
applications. For example, in the Introduction section of the tetrazole article, the
authors stress the importance of tetrazoles in coordination chemistry, medicinal
chemistry, and in various materials science applications and point out their role
as useful intermediates in the preparation of substituted tetrazoles:
Green Chemistry
Green chemistry refers to practices designed to prevent pollution and promote the sustainable use of natural resources.
P9 The literature on tetrazoles is expanding rapidly.1 This functional group
has roles in coordination chemistry as a ligand, in medicinal chemistry
as a metabolically stable surrogate for a carboxylic acid group,2 and in
various materials science applications, including specialty explosives.3
Less appreciated, but of enormous potential, are the many useful
transformations that make tetrazoles versatile intermediates en route to
substituted tetrazoles, and especially to other 5-ring heterocycles via the
Huisgen rearrangement.4 (From Demko and Sharpless, 2001)
Note that when establishing the importance of a research area, it is appropriate
to cite works that substantiate this importance. For example, 22 citations were
included in P7–P9.
Exercise 6.11
Read through the first sentences in P1–P6 again. In addition to P4, which other
passages both identify the topic and hint at its importance in the first sentence?
Exercise 6.12
Read through P10 and P11. In each case, do the following:
a. Identify the topic of the article and why the topic is important.
b. State how many citations to the literature are used to substantiate this
importance.
c. State how often the science is emphasized, rather than the scientist.
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P10 Polychlorinated biphenyls (PCBs) are a group of pollutants widely
distributed in the environment due to their generous use in the past,
their lipophilic character, and their chemical stability.1,2 Thus, PCBs
have a long environmental half-life and tend to accumulate in the food
chains; the highest concentrations were usually found in human beings
and higher animals at the top of the food chain.3,4
Food, and especially fatty food, has been widely recognized as
the main source of intake of toxic chemicals such as PCBs.5 Dairy
products, and milk in particular, have received special interest due to
their extensive and elevated consumption by the population.6 Several
countries have established levels (recommended maximum limits,
RMLs) for PCBs in dietary products such as fish (~2000 ng/g), meats
(ranging from 200 to 2000 ng/g), and eggs (100–300 ng/g). For milk
and dairy products, RMLs range from 200 (Canada) to 1500 ng/g
(Thailand). Germany has established RMLs for some congeners (PCBs
28, 52, 101, 180) in 8 ng/g of fat and 10 ng/g of food, for the food with
more and less than 10% fat, respectively.7 (From Llompart et al., 2001)
P11 The asymmetric synthesis of α-amino acids and derivatives is an
important topic as a result of their extensive use in pharmaceuticals
and agrochemicals and as chiral ligands. Many highly enantioselective
approaches have been reported.1 Industrial production of α-amino acids
via the Strecker reaction is historically one of the most versatile methods
to obtain these compounds in a cost-effective manner, making use of
inexpensive and easily accessible starting materials.2 (From Boesten
et al., 2001)
Exercise 6.13
Browse through three different chemistry journals. To make this exercise more
relevant, choose journals related to your own field of study. For each journal,
write down the name of the journal and three themes used to justify the importance of works in the journal.
When authors cite others’ works to establish the importance of their own work
(discussed above), or to provide background information (discussed below), they
frequently use present tense. You might find this surprising because, after all, the
cited works were done in the past; yet, the importance of the work is expected to
be true today and into the future. Consider the following example:
P12 This functional group has roles in coordination chemistry as a
ligand, in medicinal chemistry as a metabolically stable surrogate
Writing the Introduction Section
213
for a carboxylic acid group,2 and in various materials science
applications, including specialty explosives.3 (From Demko and
Sharpless, 2001)
It would sound funny to say, in the past tense, that the functional group “had”
roles in coordination chemistry, implying that those roles are no longer important. In addition to present tense, another verb construction is commonly used
when citing others’ works. Consider the following sentence:
P13 In numerous studies, Cr6+ compounds have been shown to be
carcinogenic in vivo and mutagenic in vitro. (From Plaper et al., 2002)
The construction “have been shown” (in P13) is an example of a verb form known
as present perfect. There are two forms of the present perfect:
Present perfect–active has shown, have shown
Present perfect–passive has been shown, have been shown
Present perfect is typically used to signal that the knowledge gained from work
completed in the past is still believed to be true in the present. Present perfect combines has or have with a past-participle verb form, which is usually (but
not always) the same as the past tense form (see table 6.2). Note that the use of
the present perfect is not limited to this submove; you will see it used in other
sections of the journal article, as well.
Table 6.2 Examples of active and passive constructions in present perfect.
Active Voice: has/have + past
participlea
Passive Voice: has/have + been + past
participlea
has demonstrated
has been demonstrated
has recognized
has been recognized
has shown
has been shown
have discovered
have been discovered
have observed
have been observed
have received
have been received
a. Present perfect and passive voice constructions require the use of the past participle. For
most regular verbs, the past tense and the past participle verb forms are the same (e.g., for the
verb “demonstrate”, both the past tense and past participle are “demonstrated”). With many
irregular verbs, however, the past tense and past participle verb forms are different (e.g., for
the verb “show”, the past tense is “showed” but the past participle is “shown”). Common past
participles include the following: become, chosen, given, grown, seen, shown, taken, undergone,
undertaken.
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Present Tense and Present Perfect
When citing others’ works to establish importance or provide background information,
authors often use present tense or present perfect in either active or passive voice.
Present tense–active
Nagy et al. (1) propose . . .
Present tense–passive Arsenic is recognized as . . . (1).
Present perfect–active Nagy et al. (1) have proposed . . .
Present perfect–passive Arsenic has been recognized as . . . (1)
Verb Forms
Native speakers of English will likely hear the difference between the past tense and past
participle forms of the verb and use them appropriately, even if they do not know the terminology used to distinguish one from the other. Hence, “it has been showed” will sound
wrong and “it has been shown” will sound right.
For nonnative speakers, however, it is helpful to know the different verb forms and the
rules behind what “sounds right” to the native ear.
Exercise 6.14
The following passages comprise the first several sentences of two articles from
the same issue of the Journal of Agricultural and Food Chemistry. Make a list of the
present tense and present perfect verb constructions used in each passage. Which
construction do the authors seem to prefer?
a. Progress in plant lectin biochemistry has exploded during the past
decade (1). New lectins with interesting properties have been isolated and
characterized; a great many lectins have been cloned, and homologies in
their amino acid sequences and similarities in their molecular structures
have been established. The X-ray crystallographic structure of a host of these
lectins has been solved at high atomic resolution. The biosynthesis of many
lectins has been elucidated. Many lectins have been expressed in bacteria
and eukaryotic cells and their mutant forms studied to determine changes, if
any, in their carbohydrate-binding specificity. A number of lectins have also
been transfected into food crops with the intention of conferring resistance to
various insect vectors. (Adapted from Goldstein, 2002)
b. Allium fistulosum L. (Liliaceae) is a perennial herb that is widely cultivated
throughout the world, ranging from Siberia to tropical Asia. China, Japan,
and Korea grow most of the world production. The common name “Welsh
onion” derives from the German welshche, meaning foreign. Other local names
include the following: in China, Cong; in English-speaking countries, Japanese
Writing the Introduction Section
215
bunching onion, Spanish onion, two-bladed onion, spring onion, green
bunching onion, scallion, green trail, and Chinese small onion; in Japan, negi;
and in Korea, pa. It is believed to have originated in northwestern China (1).
Both the leaves and the bulbs are edible. It has also been used as an herbal
medicine for many diseases. According to the dictionary of Chinese drugs
(2), the bulbs and roots of this plant have been used for treatment of febrile
disease, headache, abdominal pain, diarrhea, snakebite, ocular disorders, and
habitual abortion, as well as having antifungal and antibacterial effects. The
seeds are used as a tonic and an aphrodisiac. (From Sang et al., 2002)
After the importance of the area has been established in the Introduction section,
the next step (submove 1.3) is to provide readers with relevant background information. The goal is to alert readers to essential works in the field, not to review
the literature exhaustively. This point is often emphasized in the Information for
Authors section provided by journals, as illustrated below for three ACS journals:
Background material should be brief and relevant to the research described.
Detailed or lengthy reviews of the literature should be avoided. (Scope,
Editorial Policy, and Preparation of Manuscripts, Chemical Research in
Toxicology 2007, 20, 12A)
The introduction should state the purpose of the investigation and must
include appropriate citations of relevant, precedent work but should not
include an extensive review of marginally related literature. (Authors’
Guide, Analytical Chemistry 2007, 79, 389)
Do not attempt a complete survey of the literature. . . . In general, the introduction should be no more than 2 double-spaced pages without figures
or tables and should include fewer than 20 references. (Instructions to
Authors, Environmental Science & Technology 2007, 29)
Despite the label assigned to submove 1.3, it is not the only submove (or move)
that presents background information; indeed, relevant background information
is (and should be) integrated throughout the Introduction section, first to introduce the topic and establish its importance, and subsequently to identify the gap
(discussed below).
To see how authors report relevant background information in their Introductions,
we consider five examples (P14–P18). As you read these passages, notice how concisely they are written. The authors do not summarize one work at a time, in whatever order they choose; instead, multiple references are grouped together in a logical
sequence, ultimately leading up to the current work. (Hints for how to achieve such
conciseness in your writing are included in part 2 of this chapter.)
Also, note that no direct quotes are used. Although common in other genres,
direct quotes are exceedingly rare in chemistry journal articles, in part, because
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space is so limited. Instead, chemistry authors must capture the essence of others’ works in only a few words or sentences. For example, consider P14; in a
single sentence, the authors summarize background information and cite nine
other works. Imagine the space it would take to directly quote from each of these
works!
P14 The most common cleanup methods are as follows: shaking the extract
with concentrated sulfuric acid,9–12 Florisil,9–13 alumina,14,15 and silica
gel8,13 and using size exclusion chromatography (SEC).15,16 (From
Llompart et al., 2001)
Avoid Direct Quotes
Although common in other forms of writing, chemists almost never use direct quotes in
journal articles.
We next consider a passage from the article on Cr3+ toxicity. The authors have
already established the importance of chromium research in general and Cr3+
specifically (P1, P8, P13); now the authors provide background information on
what is known about Cr3+ toxicity. The authors begin by acknowledging that, so
far, Cr3+ appears to be nonmutagenic on cellular test systems; however, recent
studies indicate that Cr3+ can cause DNA damage, a finding that underscores the
need for their work.
P15 So far Cr3+ has been shown to be nonmutagenic in most of the
studies performed on cellular test systems, probably due to the inability
of the hydrated Cr3+ complexes to cross plasma membranes (10).
However, in some recent studies, Cr3+ was shown to cause Cr–DNA
adducts and DNA–DNA cross-links (13, 14). Cr3+ also increased
DNA polymerase processivity and decreased its fidelity during DNA
replication in vitro (15–17) besides causing formation of mutagenic
adducts of amino acids to the DNA phosphate backbone (18). (From
Plaper et al., 2002)
As a third example, consider a passage from the cyclodextrin article (P16). The
authors provide useful background information on two types of cyclodextrins
used in bioremediation: HPBCD and RAMEB. The two cyclodextrins are compared, and the authors explain why RAMEB was chosen over HPBCD, thereby
leading up to the current work.
P16
Two CD derivatives are most commonly used for soil remediation:
hydroxypropyl and random methylated β-cyclodextrins (HPBCD and
Writing the Introduction Section
217
RAMEB, respectively), both being mixtures of isomers with different
degree and pattern of substitution, extremely soluble in water (more
than 50%) (13), and nonvolatile. Although RAMEB has a higher
solubilizing effect, HPBCD is more feasible for the “sugar flushing”
technology because of lower surface activity (5). An aqueous solution
of RAMEB is not the best choice for soil washing because the mobility
of the nonaqueous phase liquids (NAPLs) might be increased (2). The
other unfavorable property of RAMEB may be its slight adsorption on
clay minerals (illite), whereas HPBCD is not adsorbed (14). The high
solubilizing effect of RAMEB is utilized in bioremediation techniques
requiring only low amounts (0.1–1% w/w soil) of the additive (16,
17). In this case RAMEB acts as a catalyst improving the transfer
of pollutants from the solid phase to the aqueous phase of the soil.
β-CD was also reported to improve the biodegradation of a single
hydrocarbon (dodecane) (15). γ-CD, HPBCD, and RAMEB were effective
in the intensification of PCB biodegradation in soils (10, 16). Especially
remarkable bioavailability-enhancing properties were exhibited by
RAMEB in hydrocarbon-polluted soils (17). Because soil bioremediation
needs months to years depending on type and concentration of the
contaminants, soil properties, and microflora, an additive that degrades
slowly in the soil is required. RAMEB meets this requirement. Its halflife time is about 1 year in a soil contaminated with motor oil (18),
while HPBCD is decomposed rapidly (19). (Adapted from Jozefaciuk
et al., 2003)
Numbering Citations
The citation numbers may appear to be out of sequence in P15 (because they skip from 10
to 13) and in P16 (because 13 is cited before 5 and 2), but this sequencing just means that
the missing citations were mentioned earlier in the Introduction sections. (See chapter 17.)
A fourth example (P17) is from the Introduction section of the article that
examines PCBs in full-fat milk. For background information, the authors outline the general four-step procedure used to determine PCBs in full-fat milk.
Conventional methods used to accomplish two of these steps, extraction and
cleanup, are also described. In a new paragraph, the authors introduce solidphase microextraction (SPME), a technique that greatly simplifies this four-step
process. But SPME is not recommended for complex matrixes; hence, the authors
motivate the topic of their current paper, headspace mode SPME (HSSPME).
P17
218
The general analytical procedure for the determination of PCBs in
full-fat milk includes four main steps: extraction from the matrix,
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preconcentration and cleanup steps, gas chromatographic separation,
and detection. Conventional methods of extraction are liquid-liquid
extraction and Soxhlet extraction.1 Also, solid-phase extraction (SPE)
has been employed.8 The most common cleanup methods are as follows:
shaking the extract with concentrated sulfuric acid,9–12 Florisil,9–13
alumina,14,15 and silica gel8,13 and using size exclusion chromatography
(SEC).15,16
Arthur and Pawliszyn19 introduced solid-phase microextraction
(SPME) in 1990 as a solvent-free sampling technique that reduces
the steps of extraction, cleanup, and concentration to a unique step.
SPME utilizes a small segment of fused-silica fiber coated with a
polymeric phase to extract the analytes from the sample and to
introduce them into a chromatographic system. Initially, SPME
was used to analyze pollutants in water20,21 via direct extraction.
Subsequently, SPME was applied to more complex matrixes, such
as solid samples or biological fluids. With these types of samples,
direct SPME is not recommended; nevertheless, the headspace
mode (HSSPME) is an effective alternative to extracting volatile and
semivolatile compounds from complex matrixes. (Adapted from
Llompart et al., 2001)
As a final example, consider passage P18 from the Introduction section of the
article on substituted tetrazoles. As background information, the authors examine previous efforts to synthesize 5-substituted 1H-tetrazoles and categorize these
methods into three main groups.
P18
The most convenient route to 5-substituted 1H-tetrazoles 2 is the
addition of azide ion to nitriles 1.5 The literature is replete with methods
to perform this transformation; they fall into three main categories:
those that make use of tin or silicon azides,6 those that use strong Lewis
acids,7 and those that are run in acidic media.8 (Adapted from Demko
and Sharpless, 2001)
Exercise 6.15
Consider passages P19 and P20, adapted from the Introduction sections of articles
on particulate matter and the asymmetric Strecker reaction:
a. What background information is provided in each passage?
b. Identify the verb constructions italicized in each passage as past, present, or
present perfect.
P19
It has become evident that fi ne particulate matter has the ability
to generate reactive oxygen species (ROS) (10, 11). This is striking
Writing the Introduction Section
219
because generation of ROS is intimately linked to the genesis of
pulmonary and cardiovascular injury (12). Proposed sources of
ROS include generation by particle-activated polymorphonuclear
leukocytes, and direct ROS generation by the particles themselves and/
or their constituents (13). For example, it has been reported that iron
released from airborne fi ne particles or present on their surfaces plays
a role in the generation of ROS, and this is also true for coal fly ash
particles (14–16). . . .
These pathways are thought to result in the production of
superoxide (13) or in the release of superoxide directly from the
particles themselves. Superoxide production leads to the formation of
hydrogen peroxide, and metal ions such as Fe2+ react with hydrogen
peroxide to produce the hydroxyl radical. It is well documented that
the hydroxyl radical can damage DNA as well as lipids and proteins
(18, 19). Some of the health effects of cigarette tar and smoke are
attributed to free radicals that can initiate production of superoxide
and hydroxyl radical (3, 10, 11, 20, 21). (Adapted from Dellinger
et al., 2001)
P20
Several catalytic asymmetric Strecker reactions leading to N-protected
amino nitriles in high ee and high yields have been published.4
Alternatively, diastereoselective Strecker syntheses using a broad variety
of chiral inducing agents, such as α-arylethylamines,5 β-amino alcohols
and derivatives,6 amino diols,7 sugar derivatives,8 and sulfinates,9
have been reported to provide the α-amino nitriles with varying
diastereoselectivities. (Adapted from Boesten et al., 2001)
Exercise 6.16
Consider the following direct quotation that describes lead concentrations in ice
cores and firn (loosely compacted granular snow) taken from a glacier at the
Swiss-Italian border. Convert the direct quote into a summary of the work as it
might appear in the Introduction section of a journal article on lead emissions in
the last decade.
Lead concentrations in firn dated from the 1970s are ~25 times higher than in ice dated
from the 17th century, confirming the massive rise in lead pollution in Europe during
the last few centuries. A decline of the lead concentration is then observed during the
last two decades, that is, from 1975 to 1994. . . . These variations are in good agreement
with available information on variations in anthropogenic lead emissions from West
European countries, especially from the use of lead additives in gasoline. (Adapted from
Schwikowski et al., 2004)
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6C Writing on Your Own: Draft Your Opening Paragraph
Reread the notes that you have taken on the importance of your topic and relevant background information. If you used note cards, sort them by keywords to identify multiple
works that can be grouped and cited together in your Introduction. If you did not use note
cards, figure out other ways to organize your notes by keywords or key concepts.
Begin writing your opening paragraph, including the all-important first sentence (making sure the topic is clear). Stress the importance of your research area and summarize relevant, precedent works, remembering that the key is to (1) alert your readers to works that
laid the groundwork for your study, (2) illustrate key findings in the field, and (3) summarize
essential knowledge related to the current work.
Move 2: Identify a Gap
After the importance of a research area has been identified and the relevant background information has been summarized, the Introduction section shifts from a
focus on what has been done (or learned) to an emphasis on what remains to be
done (or learned). This change in emphasis is signaled with a gap statement (table
6.1). The gap statement points out what is lacking in the field and, in so doing,
infers the next step that needs to be taken. Consider the following examples:
P21 Persistent electron paramagnetic resonance (EPR) signals have been
reported in coals, chars, and soots (26–29), but PM2.5 has not been
studied by EPR. (From Dellinger et al., 2001)
[Next step: Use EPR to study free radicals in PM2.5.]
P22 Although HSSPME has been applied to an enormous variety of
matrixes,22,24 to date, the number of publications that apply SPME
technology to milk samples is relatively low,25,26 and most of them are
related to the determination of flavors.27,28 (Adapted from Llompart
et al., 2001)
[Next step: Use HSSPME to study milk.]
P23 A major drawback of these chiral auxiliaries can be cost and/or
availability, because they are used in stoichiometric amounts and in
principle lost during the conversion. Furthermore, in many cases
the α-amino nitriles need to be purified in a separate step to obtain
diastereomerically pure compounds. Purification requires, for example,
crystallization or chromatography, which may lead to losses. (From
Boesten et al., 2001)
[Next step: Develop better chiral auxiliaries.]
P24 Because soil bioremediation needs months to years depending on type
and concentration of the contaminants, soil properties, and microflora,
Writing the Introduction Section
221
an additive that degrades slowly in the soil is required. (From Jozefaciuk
et al., 2003)
[Next step: Find slowly degrading bioremediation additives.]
Exercise 6.17
Reread P8, a passage selected to demonstrate how authors emphasize the importance of their research area (in this case, the toxicity of Cr3+). A gap statement is
also present in the passage. Find the gap statement and state it. What next step or
steps are suggested by the gap statement?
Exercise 6.18
Reread P18 and then read P25 below, which immediately follows P18 in the published article. A gap is expressed in P25. State the gap in your own words, and
identify the next step that is implied.
P25 Each of these [previous methods] involves one or more of the following
drawbacks: uses expensive and toxic metals, demonstrates severe
water sensitivity, or produces hydrazoic acid, which is highly toxic
and explosive as well as volatile. The few methods that seek to avoid
hydrazoic acid liberation during the reaction, by avoiding acidic
conditions, require a very large excess of sodium azide.9 In addition,
all of the known methods use organic solvents, in particular, dipolar
aprotic solvents such as DMF. This is one of the solvent classes that
process chemists would rather not use.10 (Adapted from Demko and
Sharpless, 2001)
Exercise 6.19
Select three different chemistry-specific journals. In each journal, find two articles that include gap statements in their Introduction sections. Write down the
name of the journal, the gap statement (either restated or verbatim), and the location of the gap statement (near the beginning, middle, or end of the Introduction).
Comment on whether the gap statement serves as a transition between describing
previous work and the current work.
6D Writing on Your Own: Identify a Gap
Make a list of the possible gaps that your work fills. For each gap, consider the conclusions
that might be drawn by your readers. Identify references that will support your claims.
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Move 3: Fill the Gap
After the gap has been established, the last move of the Introduction section is to
fill the gap. The authors must show how the current work takes at least a small
step forward toward addressing the specified need, problem, or lack of knowledge
in the field. The start of the third move is commonly signaled with a new paragraph and a phrase such as “In this paper,” or “In this work, we . . . ” (see table 6.3).
Following this phrase, the authors go on, typically in a sentence or two, to tell the
readers about the current work. Four examples are given below:
P26 In this article, a simple and rapid saponification-HSSPME procedure has
been developed for the extraction of PCBs from different milk samples.
Saponification of the fats helps the transference of the PCBs from the
sample to the microextraction fiber. Moreover, saponification acts as
a cleanup step, thereby improving selectivity and reliability in peak
identification. (Adapted from Llompart et al., 2001)
P27 In this article, we report the results of studies that indicate that PM2.5
does indeed contain semiquinone-type radicals, and these radicals
can initiate damage to DNA through a catalytic cycle involving ROS.
(Adapted from Dellinger et al., 2001)
P28 In this article, the first two examples of the use of (R)-phenylglycine
amide in asymmetric Strecker reactions are presented. (Adapted from
Boesten et al., 2001)
P29 To assess the influence of Cr3+ on the eukaryotic cells, its effect on
the viability and proliferation rate of murine B16 melanoma cells,
and . . . human epithelial cells was tested. (From Plaper et al., 2002)
The phrases in table 6.3 are often followed by the personal pronoun we (e.g., In
the present study, we . . . ). In such instances, we is used to signal the beginning
of the authors’ presented work in the journal article. (Recall that we is also used
in Results sections to signal human choice and in Discussion sections to signal
interpretative remarks.) Table 6.4 lists some verbs that typically follow we in the
fill-the-gap statement. Note that the verbs are in present tense when they refer to
what is presented in the paper (e.g., “we present”); they are in past tense when
they refer to work done in the past (e.g., “we measured”). (See table 6.5 for a summary of common functions of verb tense–voice combinations in Introductions.)
Table 6.3 Common phrases used to transition from the second to the third move of
the Introduction section.a
In the present study,
In this context,
In this study,
In this paper,
In the present work,
In this investigation,
In this work,
Herein,
a. These phrases were identified through a computer-based analysis of Introduction sections
from 60 published chemistry journal articles.
Writing the Introduction Section
223
Table 6.4 Common verbs that follow we in the fill-the-gap statement of the Introduction
section.a
In this work, we (present tense verbs)
In this work, we (past tense verbs)
carry out
analyzed
demonstrate
calculated
describe
chose
develop
determined
employ
employed
present
examined
propose
focused on
provide
found
report
investigated
show
measured
use
solved
studied
synthesized
a. These phrases were identified, in part, through a computer-based analysis of Introductions from
60 published chemistry journal articles.
Words to Avoid
When introducing the current work, avoid informal phrases such as “we looked into”, “we
looked at”, “we saw if”. See Formal Vocabulary in appendix A.
On occasion, a fill-the-gap statement will appear in the opening paragraph of
the Introduction section. This deviation from the conventional move structure in
figure 6.1 is particularly common in organic journals such as The Journal of Organic
Chemistry. Moreover, in such journals, the authors often include more than one
fill-the-gap statement. For example, in the tetrazole article, Demko and Sharpless
(2001) include fill-the-gap statements at the end of their first (P30), second (P31),
and fourth paragraphs (P32). (The final paragraph of their Introduction section
previews principal findings, as shown in P36 later in this chapter.) Each fill-thegap statement emphasizes steps taken (in this case, to advance the use of water as
a solvent in organic reactions).
P30 (Fill-the-gap statement in first paragraph) We report here a safer and
exceptionally efficient process for transforming nitriles into tetrazoles in
water; the only other reagents are sodium azide and a zinc salt.
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Table 6.5 Common functions of different verb tense–voice combinations in Introduction sections.
Function
Tense–Voice
Combination
Example
To introduce research
area
Present–active
Chromium is a metal widely distributed in
soil and plants (1). (From Plaper et al., 2002)
To describe importance
of the research area
Present–active
PCBs have a long environmental half-life
and tend to accumulate in the food chains.
(From Llompart et al., 2001)
Present perfect (active
and passive)
Many highly enantioselective approaches
have been reported.1 (From Boesten et al.,
2001) (present perfect–passive)
Present active
Present perfect (active or
passive)
Conventional methods of extraction
are liquid-liquid extraction and Soxhlet
extraction.1 Also, solid-phase extraction
(SPE) has been employed.8 (From Llompart
et al., 2001) (present active; present
perfect–passive)
Past–active
In some recent studies, . . . Cr3+ increased
DNA polymerase processivity and decreased
its fidelity during DNA replication in vitro
(15–17). (Adapted from Plaper et al., 2002)
Present–active
[A]n additive that degrades slowly in the soil
is required. (From Jozefaciuk et al., 2003)
Present perfect–passive
PM 2.5 has not been studied by EPR. (From
Dellinger et al., 2001)
Present–active
In this paper, we report the results of
studies that . . . (Adapted from Dellinger
et al., 2001)
Past (active or passive)
In this work, we adapted a method for
the analysis of . . . (Vesely et al., 2003)
(past–active)
Past (active and passive)
Present–active
During the study, it was discovered that Cr3+
causes DNA damage, has influence on DNA
topology, most probably via effects on DNA
gyrase, and also reduces the proliferation
rate of certain eukaryotic cells. (From Plaper
et al., 2002) (past–passive; present–active)
To provide relevant
background
information
To identify a gap
To introduce the
current work (as a
means to fill the gap)
To hint at fi ndings,
focusing on work done
in the past and/or
“truths” gleaned from
the research
Writing the Introduction Section
225
P31 (Fill-the-gap statement in second paragraph) We sought a method that
avoided these drawbacks and was easy to use on both a laboratory and
industrial scale.
P32 (Fill-the-gap statement in fourth paragraph) Thus encouraged, we
envision a special style of organic synthesis, one based on an entire
family of reactions for which water is the best “solvent.”
The fill-the-gap statement is an appropriate way to end the Introduction section.
For example, Dellinger et al. (2001) conclude their Introduction with the fill-thegap statement in P27. Alternatively, some authors elect to end their Introductions
by previewing a principal finding (optional submove 3.2 in figure 6.1). We consider
four examples, each only a sentence or two in length. The first (P33) previews
an experimental method, because the focus of this work was to develop a more
accurate and sensitive technique. The others preview major findings. Note also
the use of present and past tense in these passages. Past-tense verbs (italicized)
are used to refer to work done in the past; present-tense verbs (bolded) are used
to describe “truths” gleaned from the research. (See table 6.5 for a summary of
common functions of verb tense–voice combinations in Introduction sections.)
P33 Analyses were performed on a gas chromatograph equipped with an
electron capture detector (ECD) and a gas chromatograph coupled
to a mass-selective detector working in mass spectrometry-mass
spectrometry (MS-MS) mode, to achieve better limits of detection and
selectivity. The proposed method yields high sensitivity, good linearity,
precision, and accuracy. (From Dellinger et al., 2001)
P34 During the study, it was discovered that Cr3+ causes DNA damage, has
influence on DNA topology, most probably via effects on DNA gyrase,
and also reduces the proliferation rate of certain eukaryotic cells. (From
Plaper et al., 2002)
P35 Pivaldehyde and 3,4-dimethoxyphenylacetone were used as starting
materials, which lead, respectively, to enantiomerically enriched
tert-leucine and α-methyl-dopa, two important nonproteogenic
α-amino acids for pharmaceutical applications. In addition, tert-leucine
has considerable utility as a chiral building block.14 (From Boesten
et al., 2001)
P36 As a result of these endeavors, we found that in the presence of zinc
salts9b,c tetrazole formation proceeds with excellent yields and scope in
refluxing water.16 Thanks to the low pK a of 1H-tetrazoles (ca. 3–5) and
their highly crystalline nature, a simple acidification is usually sufficient
to provide the pure tetrazoles. (Adapted from Demko and Sharpless,
2001)
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Exercise 6.20
Table 6.3 lists common phrases used to transition from the second to the third
move of an Introduction section. Select two or three journals of your choice;
browse through the Introductions in these journals until you find three new ways
to introduce the third move of the Introduction. Remember that you will most
often see these phrases toward the end of the Introduction section. Add these new
phrases to table 6.3 to make it more complete.
Exercise 6.21
Select two journals of your choice and then select two Introduction sections in
each journal. Examine how the authors end their Introductions.
a. Do the Introduction sections conclude with submove 3.1, 3.2, or a variation?
Support your answer with excerpts from the Introductions.
b. Comment on how the authors use past tense and present tense in these
excerpts. (Refer to table 6.5, if needed.)
6E Writing on Your Own: Draft Your Full Introduction
Following the move structure of an Introduction section, as shown in figure 6.1, write a
draft of your full Introduction.
Check the all-important opening sentence that you drafted as part of Writing on Your
Own task 6C. Did you identify the topic of your paper?
When describing the importance of your research area, focus on the research rather than
the researchers. When presenting background information, paraphrase the work of others;
do not use direct quotations. When filling the gap, remember to introduce your work by
using one of the phrases in table 6.3. Decide whether you want to report principal findings.
After you have completed a good draft, insert citations and begin your reference list (if
you have not started it already). Refer to chapter 17 for guidelines on formatting citations
and references.
Part 2: Writing Concisely and Fluidly
I always take my writing seriously. Although I don’t know my readers,
they all meet me through my writing. I want my words to communicate
my commitment to good science, my professionalism, and my desire to
engage in a dialogue with the larger scientific community.
—David B. Knaff, Texas Tech University
Writing the Introduction Section
227
It is not easy to write a clear and concise Introduction. Before pen is put to paper
(or fingers to keyboard), authors must first find, read, and understand appropriate literature and consolidate key concepts, trends, and fi ndings. Next, they must
organize this information in a logical order, linking like concepts in fluent prose,
using language that is neither repetitive nor choppy. These are not trivial writing
skills, even for an experienced writer. Here we focus on ways to help you develop
these writing abilities, targeting conciseness and fluidity. These practices apply
not only to the Introduction section but to other parts of the journal article, and
to other genres as well.
Be Concise
When beginning writers first attempt to summarize others’ works, they often do
so using a wordy and repetitive writing style. For example, when multiple works
are cited, novice writers often resort to the following monotonous pattern:
Garcia et al.1 showed . . . Daloğlu et al.2 showed . . . Manygoats et al.3 showed . . .
Or worse (because it is wordier), inexperienced writers might compose the
following:
In a study by Garcia et al.1, it was shown that. . . . Another study was conducted by
Daloğlu et al.2 to show that. . . . In a more recent study conducted by the scientists
Manygoats et al.,3 additional evidence was provided to show that. . . . Finally, other
researchers4–6 have shown that. . . .
Although nothing is wrong grammatically with the sentences above (even et
al. is used correctly), they signal a novice writer because they are wordy and
include unconventional words such as researcher and scientist. More important,
the wordiness of the sentences interferes with clarity. To enhance the clarity and
conciseness of your writing, consider the following two suggestions (discussed
in more detail below): (1) focus on the science, not the scientist(s), and (2) group
related ideas.
Concise Writing
See appendix A.
Researchers and Research
In a computer-based analysis of Introduction sections from 60 published chemistry journal
articles, there were no occurrences of the term researchers.
The term research, used infrequently, rarely refers to authors’ own work or the work of
others. Rather, the term research, when used, usually has a more generic sense:
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A key element in genetics research is . . .
Many theoretical and experimental research studies on optical nonlinearity of
fullerene . . .
Surprisingly little research has been reported on SBA-1 . . .
Research in this area has involved multicomponent molecules . . .
Recommendations:
Use the term research sparingly.
Do not use the term researchers.
The first suggestion to make your writing more concise is to eliminate the names
of scientists and the titles of their works from your sentences. (If relevant, this
information is included in the references, so it is redundant to repeat it in the
text.) The authors of the six key articles in this textbook followed this advice;
more than 125 articles were cited in their Introduction sections, but authors’
names appeared only once! What this means, then, is to make the science the
subject of your sentences. Consider the following examples:
Very wordy In their article titled “Preparation of 5-Substituted 1H-Tetrazoles
from Nitriles in Water,” Demko and Sharpless5 propose a way
to synthesize 1H-tetrazoles using nitriles and sodium azide in
water.
Wordy
Demko and Sharpless5 recently proposed a way to synthesize
1H-tetrazoles using nitriles and sodium azide in water.
Concise
1H-tetrazoles have been prepared using nitriles and sodium
azide in water.5
Exercise 6.22
Revise the following sentences so that the names of all scientists, article titles,
and book titles have been removed. How many fewer words are needed? Does the
conciseness aid or detract from the readability of the sentences?
a. Molnar et al. (17) were among the first scientists to point out that remarkable bioavailability-enhancing properties are exhibited by RAMEB in
hydrocarbon-polluted soils. (Adapted from Jozefaciuk et al., 2003) (24 words)
b. Fatty foods, as first suggested by the researchers Gallo et al.,5 are widely recognized as a main source of intake of toxic chemicals such as PCBs. (Adapted
from Llompart et al., 2001) (26 words)
c. Reichardt,11 in his important book titled Solvents and Solvent Effects in Organic
Chemistry, asserted that water has extraordinary physical properties as
Writing the Introduction Section
229
a solvent, making its use as a solvent widely appreciated. (Adapted from
Demko and Sharpless, 2001) (31 words)
A second strategy for achieving conciseness requires that you group related ideas
and use punctuation appropriately. For example, when summarizing the literature, introduce related ideas with the phrase such as. Consider the following
examples, juxtaposing a fabricated wordy passage with its more concise (authentic) counterpart:
Wordy
Several countries have established levels (recommended
maximum limits, RMLs) for PCBs in dietary products. Levels of
~2000 ng/g have been established for fi sh. Levels ranging from
200 to 2000 ng/g have been established for meats. Levels between
100 and 300 ng/g have been established for eggs. (4 sentences,
46 words)
Concise Several countries have established levels (recommended
maximum limits, RMLs) for PCBs in dietary products, such as fish
(~2000 ng/g), meats (200–2000 ng/g), and eggs (100–300 ng/g).
(adapted from Llompart et al., 2001) (1 sentence, 28 words)
An alternative way to achieve conciseness is to use the word respectively:
Concise Several countries have established levels (recommended maximum
limits, RMLs) for PCBs in dietary products, such as fish, meats,
and eggs, with RMLs of ~2000, 200–2000, and 100–300 ng/g,
respectively. (1 sentence, 31 words)
Respectively
See appendix A and chapter 4.
The use of colons, with grouped ideas, can also contribute to conciseness. In the
following examples, the fabricated wordy passage uses no colon; the more concise
(authentic) passage lists the related items after a colon:
Wordy
230
The general analytical procedure for the determination of
PCBs in full-fat milk includes four main steps. This first step
involves extraction of the PCBs from the matrix. The second step
involves preconcentration and cleanup. The third step uses gas
chromatographic separation. Finally, the last step involves detection.
(5 sentences, 47 words)
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Concise The general analytical procedure for the determination of PCBs in
full-fat milk includes four main steps: extraction from the matrix,
preconcentration and cleanup, gas chromatographic separation, and
detection. (From Llompart et al., 2001) (1 sentence, 28 words)
Note that when you use a colon, it must be preceded by a complete sentence:
Incorrect The procedure includes: extraction, cleanup, and detection.
Correct The procedure includes three steps: extraction, cleanup, and
detection.
Commas, Colons, and Semicolons
See appendix A.
Items grouped in a series may also be numbered (with numbers enclosed in
parentheses) to achieve conciseness.
Wordy
Over the past few years, we have encountered numerous examples
of water as the “perfect” solvent. We observed this first in osmiumcatalyzed dihydroxylation reactions12 and also in nucleophilic
ring-opening reactions of epoxides.13 We also observed this in
cycloaddition reactions13 and in most oxime ether, hydrazone, and
aromatic heterocycle condensation processes.14 Finally, we observed
it in formation reactions of an amide from a primary amine and
an acid chloride using aqueous Schotten-Baumann conditions.15
(4 sentences, 72 words)
Concise Over the past few years, we have encountered numerous examples
of water as the “perfect” solvent in, for example, (1) osmiumcatalyzed dihydroxylation reactions;12 (2) nucleophilic ring-opening
reactions of epoxides;13 (3) cycloaddition reactions;13 (4) most
oxime ether, hydrazone, and aromatic heterocycle condensation
processes;14 and (5) formation reactions of an amide from a
primary amine and an acid chloride using aqueous SchottenBaumann conditions.15 (Adapted from Demko and Sharpless, 2001)
(1 sentence, 61 words)
When grouping related items to achieve conciseness, pay careful attention to parallelism. The preceding examples illustrate two types of parallelism:
Plural nouns
fish, meats, and eggs
reactions, epoxides, and processes
Nominalizations extraction, preconcentration, separation, and detection
Writing the Introduction Section
231
Parallelism
See appendix A.
Exercise 6.23
Imagine that you are writing a paper on lead concentrations in particulate matter
in Houston, Texas. You want to summarize the results of Smith and Caine (2007)
in your Introduction section. Your notes are given below. Convert your notes into
one or two concise sentences for your Introduction, grouping related items with
one of the patterns described above. Check your sentence(s) for proper punctuation and parallelism.
Sara Smith & Tim Caine (2007) studied lead concentrations in particulate matter in
Pittsburgh. They wanted to see how much lead there was in the particulate and what the
sources of the lead might be. They found about 65% of the lead was from diesel vehicles.
About 20% was from emissions from nondiesel vehicles. The remaining 15% was from
industrial emissions. The lead concentrations were reported to be somewhere between
2 and 20 parts per billion (ppb).
Exercise 6.24
Imagine you are writing a paper about carbon nanotubes (CNTs). In your
Introduction section, you want to summarize some unique properties of CNTs
that are reported in the literature. You have listed these in your notes, given below.
Convert your notes into one or two concise sentences for your Introduction,
grouping related items with one of the patterns described above. Check your
sentence(s) for proper punctuation and parallelism.
232
■
CNT have very strong tensile strength with a mean Young’s modulus value of
1002 GPa (Yu et al., 2008)
■
CNTs have unusually high thermal conductivity (Hone et al., 2007)
■
CNTs conduct electricity ballistically (implying a bullet-like trajectory) and as
a result do not create resistive heating when they conduct electricity (Frank
et al., 1999)
■
CNTs can be manipulated to display properties of either semiconductors or
metallic conductors (Collins et al., 2006)
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Be Fluid
Experienced writers know how to make their words flow, logically linking
thoughts and ideas. One way to achieve fluidity in your writing, particularly in
the Introduction section, is to use words or short phrases that create obvious
linkages between sentences and/or add emphases to your writing. Consider the
italicized examples below. Note how many of these words and phrases are followed by a comma.
a. Furthermore, large volumes of organic solvents are used and significant
amounts of residues are generated. (From Llompart et al., 2001)
b. Subsequently, SPME was applied to more complex matrixes, such as solid
samples or biological fluids. (From Llompart et al., 2001)
c. For example, it has been reported that iron released from airborne fine particles or present on their surfaces plays a role in the generation of ROS, and
this is also true for coal fly ash particles (14–16). (From Dellinger et al., 2001)
d. As a result of these endeavors, we have found that in the presence of zinc
salts9b,c tetrazole formation proceeds with excellent yields and scope in
refluxing water.16 (From Demko and Sharpless, 2001)
e. Moreover, saponification acts as a cleanup step and then improves selectivity
and reliability in peak identification. (Adapted from Llompart et al., 2001)
f. However, these methods are rather complicated and not highly selective.
(From Vesely et al., 2003)
g. Thus, PCBs have a long environmental half-life and tend to accumulate in the
food chains; the highest concentrations were usually found in human beings
and higher animals at the top of the food chain.3,4 (From Llompart et al., 2001)
h. In numerous studies, Cr6+ compounds have been shown to be carcinogenic in
vivo and mutagenic in vitro. (From Plaper et al., 2002)
i. In contrast to Cr6+, trivalent chromium (Cr3+) is actually an essential nutrient,
needed for the expression of glucose tolerance (1). (From Plaper et al., 2002)
Words and phrases such as these are also used in the middle of sentences or
between sentences connected by a semicolon. Consider these passages, paying
special attention to the ways in which commas and semicolons are used.
a. Dairy products, and milk in particular, have received special interest due
to their extensive and elevated consumption by the population.6 (From
Llompart et al., 2001)
b. With these types of samples, direct SPME is not recommended; nevertheless,
the headspace mode (HSSPME) is an effective alternative to extracting volatile and semivolatile compounds from complex matrixes. (From Llompart
et al., 2001)
Writing the Introduction Section
233
c. It is therefore important that Cr3+ toxicity be investigated in further detail, to
ensure safer application of this additive. (From Plaper et al., 2002)
d. Purification requires, for example, crystallization or chromatography, which
may lead to losses. (From Boesten et al., 2001)
e. Although HSSPME has been applied to an enormous variety of matrixes,22,24
to date, the number of publications that apply SPME technology to milk
samples is relatively low,25,26 and most of them are related to the determination of flavors.27,28 (Adapted from Llompart et al., 2001)
Fluid Writing
See appendix A.
When used properly, such words and phrases contribute to the flow of the written passage. Of course, their use is not confined to the Introduction section of a
journal article (although all the examples here come from Introductions). When
used appropriately, and in the right places, such words and phrases add cohesiveness to a journal article as a whole. A list of useful phrases, organized by their
common functions, is presented in table 6.6. Many, but not all, of these phrases
are conventionally followed by commas when they start a sentence.
Exercise 6.25
Read the following passage. Do the italicized terms serve the functions indicated
in table 6.6? If not, what functions do they serve to create a cohesive passage?
Initially, SPME was used to analyze pollutants in water20,21 via direct extraction.
Subsequently, SPME was applied to more complex matrixes, such as solid samples
or biological fluids. With these types of samples, direct SPME is not recommended;
nevertheless, the headspace mode (HSSPME) is an effective alternative to extracting volatile and semivolatile compounds from complex matrixes. (From Llompart
et al., 2001)
Exercise 6.26
Read the following passage. Two words (or phrases) are missing, indicated by
the blanks. What words do you think the authors used? Does the inclusion of
these words add a sense of fluency to the passage? Do the words add clarity to
the passage?
Laser ablation coupled to ion cyclotron resonance Fourier transform mass spectrometry (in both positive and negative ion modes) can be used to distinguish natural and
234
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artificial opals. In positive ion mode, species including hafnium and large amounts of
zirconium atoms are found to be specific for artificial opal. ____, aluminum, titanium,
iron, and rubidium are systematically detected in the study of natural opals. ____, some
ions allow us to distinguish between natural opal from Australia and Mexico. Australian
gemstones include specifically strontium, cesium, and barium. (Adapted from Erel
et al., 2003)
Exercise 6.27
Browse through the Introduction sections of three different journal articles and
find at least five examples of sentences that begin with a word or short phrase that
serves one or more of the functions listed in table 6.6.
Table 6.6 Common phrases used to create linkages and their functions.a
To show contrast
Conversely,
However,
In contrast,
Nevertheless,
On the other hand,
Unfortunately,
To provide additional information
Additionally,
Furthermore,
In addition,
Moreover,
Namely,
To describe a typical case
In general,
Typically,
Usually,
To show cause and effect
Accordingly,
As a consequence,
As a result,
Consequently,
Hence,
Therefore,
Thus,
To this end,
To give examples
For example,
For instance,
To add emphasis or clarify
In particular,
More specifically,
Specifically,
To signal time
Afterward,
Initially,
Previously,
Simultaneously,
Subsequently,
To date,
Ultimately,
To refer to something previously stated
As mentioned/described above,
In the latter case,
In this/these/that/those cases(s),
In this context,
In this respect,
a. These phrases were identified through a computer-based analysis of Introductions from 60
published chemistry journal articles.
Writing the Introduction Section
235
6F Writing on Your Own: Practice Peer Review
Before you review a peer’s Introduction section, practice the peer review process. Imagine
that a colleague has asked you for feedback on an Introduction that is currently in draft
form. Based on what you have learned in this chapter, read the draft and instructions
(included in “Peer Review Practice: Introduction Section” at the end of the chapter) and
offer written suggestions for improving the draft.
6G Writing on Your Own: Fine-Tune Your Introduction
By now, you should have a good draft of your Introduction section, having completed the
previous Writing on Your Own tasks. Now it is time to revise and edit your Introduction as a
whole, using the suggestions provided in the chapter.
Refer to chapter 18 and the questions below to guide you in the revision process. Be
sure to focus on each of the following areas:
1. Organization of text: Check your overall organizational structure. Did you follow the
move structure outlined in figure 6.1?
2. Audience and conciseness: Will your Introduction draw readers into the paper? Is it written for a broader audience, moving from a general focus to a more specific focus? Have
you taken steps to ensure that your writing is concise? Find at least three sentences that
can be written more clearly and concisely.
3. Writing conventions: Check to be sure that you have (1) not used direct quotes;
(2) paraphrased the literature accurately, giving credit (in the form of citations) where
it is due; (3) focused on the science rather than the scientists; (4) used tense and voice
purposefully; and (5) created linkages between sentences to enhance the fluidity of
your written work.
4. Grammar and mechanics: Check for typos and errors in spelling, subject–verb agreement, parallelism, and punctuation, paying special attention to your more complex
sentences.
5. Science content: Have you correctly conveyed the science of others, and your own? If
asked, could you define all of the words you have used in this section?
After thoroughly reviewing your own work, it is common practice to have your work
reviewed by a peer or colleague. A “new set of eyes” will pick up mistakes that you can no
longer see because you are too familiar with your own writing. To facilitate this process,
use the Peer Review Memo on the Write Like a Chemist Web site. After your paper has
been reviewed (and you have reviewed another’s paper), make final changes in your
Introduction section.
236
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Finalizing Your Written Work
See chapter 18.
Chapter Review
As a self-test of what you’ve learned in this chapter, define each of the following
terms for a friend or colleague who is new to the field:
background information
current work
direct quotes
fill-the-gap statement
gap statement
green chemistry
linking words
parallelism
present perfect
review of the literature
Also explain the following to a friend who hasn’t yet given much thought to writing an Introduction section for a journal article:
■
Main purposes of an Introduction section
■
Moves of an Introduction
■
Role of a gap statement in an Introduction
■
Types of gaps often identified in an Introduction
■
Use of present, past, and present perfect in an Introduction
■
Place of direct quotations and paraphrasing in an Introduction
■
Common techniques for making writing more concise and fluid
Additional Exercises
Exercise 6.28
Read the following two passages. Which move in the Introduction does each passage correspond to? (Consult figure 6.1.) Rewrite each passage so that it follows
the writing conventions of the corresponding move more closely:
a. In the paper that we wrote and have presented below, we make use of fluorescence to accomplish the characterization of the coil-globule transition of
isolated PEO chains in toluene. (Adapted from Farinha et al., 2001)
Writing the Introduction Section
237
b. A particular type of damage caused by free radicals known as oxidative damage has been associated with vascular disease in people with types 1 and 2
diabetes mellitus (DM) (2). There are several different potential sources of
this free radical production in diabetics. For example, one possible source is
autoxidation of plasma glucose (4). Another possible source is if the leucocytes get activated (5). A third possible source is if the bioavailability of
transition metals is increased (6). (Adapted from Cheng et al., 2004)
Exercise 6.29
Reflect on what you have learned about writing an Introduction section for a
journal article. Select one of the reflection tasks below and write a thoughtful and
thorough response:
a. Reflect on the unique characteristics of an Introduction to a journal article.
■
■
■
In what ways is an Introduction different from the Methods, Results, and
Discussion sections of a journal article?
In what ways is an Introduction similar to the other sections of a journal
article?
Which part of an Introduction do you think is most critical?
b. Reflect on the role of a literature review in an Introduction.
■
■
■
Why is a literature review so important?
What factors should you consider when deciding which articles to include
in or exclude from your own literature review?
When reading the primary literature, what should you concentrate on for
your Introduction?
c. Reflect on the three moves of an Introduction section.
■
■
■
As a writer, what challenges do you associate with each move (and corresponding submoves)?
Why is the opening sentence of an Introduction so important?
Do you think it is a good idea to conclude an Introduction with a final
paragraph that summarizes key findings? Or do you think readers should
be patient and discover key findings later in the paper, in the Results
section? Explain.
Peer Review Practice: Introduction Section
Imagine that a colleague has asked you to review an Introduction that is currently in draft form; your colleague plans to use your feedback to improve the
written work.
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Using parts 2 and 3 of the Peer Review Memo on the Write Like a Chemist Web
site, review the Introduction below. Remember to give suggestions that are specific
enough to guide your colleague in improving the Introduction. (The Introduction
below is adapted from an original source, noted in the Instructor’s Answer Key.)
1
Toxicology is the study of harmful effects of chemicals on people, animals and other
2 living organisms. Forensic toxicology involves the analysis of drugs and poisons in
3 biological specimens. It also involves the interpretation of the results to be applied in a
4 court of law. Availability of analytical reference standards becomes a critical factor when
5 a novel target substance is encountered. Reference standards are also important when
6 a comprehensive screening procedure is updated. Commercial drugs can be acquired
7 within a reasonable period of time. Their metabolites generally cannot. The situation is
8 even more complicated in the rapidly changing scene of designer drugs. Identification
9 of low-dose substances in biomatrixes without reference standards is a challenge to any
10 well-equipped research laboratory. The forensic analyst in charge usually has to be satis11 fied with comparing sample mass spectra to those published in electronic libraries for
12 electron impact gas chromatography/mass spectrometry (GC/MS).
13
Marquet1 suggests that the number of liquid chromatography/mass spectrometry
14 (LC/MS) applications in forensic toxicological analysis has increased markedly during
15 the past decade. In comprehensive drug screening, identification has been based on
16 fragment ions or comparison of full mass spectra. This necessitates reference substances
17 for the construction of spectra libraries. Several researchers question the interlaboratory
18 reproducibility of mass spectral libraries obtained by these techniques.2–4 This lack of
19 reproducibility hinders the creation of universal reference libraries.
20
Burlingame5 and Lewis et. al6 use accurate mass in the monitoring of specific
21 compounds in environmental and biological samples with glass capillary gas chroma22 tography/high-resolution mass spectrometry. This approach is limited by expensive
23 instrumentation. Orthogonal acceleration time-of-fl ight mass spectrometry (OATOFMS)
24 allows continuous mass measurement with moderate resolution (5000) and high mass
25 accuracy (5 ppm). Several affordable benchtop liquid chromatography/time-of-flight
26 mass spectrometry (LC/TOFMS) instruments were recently launched onto the market.
27 The accurate mass measurement enables formulation of candidate elemental com28 positions for a particular mass. This allows tentative characterization of substances.
29 Predefined exact masses can be searched for identification. A number of studies use
30 OATOFMS in the identification and characterization of: unknown drug metabolites,
31 glucuronide conjugates, pesticides, anabolic steroids, and quantitative drug analysis.7–15
32
A preliminary communication from this laboratory introduced the concept of urine
33 drug screening by positive pneumatically assisted electrospray ionization LC/TOFMS
34 with an automated target library search based on elemental formulas.16 This approach
35 was based on the assumption that tentative identification of drugs in urine is viable
36 without reference standards by use of exact monoisotopic masses and metabolite pat37 terns from the literature. The present study evaluated this screening methodology to the
38 full with a series of urine samples taken at autopsy. It showed the scope and limitations
39 of this method in forensic toxicology practice.
Writing the Introduction Section
239
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7
Writing the Abstract and Title
The purpose of the abstract is to inform, to give away the punch
line right at the start, and to let your readers decide whether
they want to read the full document. Scientific writing is not like
mystery writing in which the results are hidden until the end.
—Adapted from Alley (1996)
This chapter addresses how to write abstracts and titles for journal articles. Both
the abstract and title provide succinct, informative (not descriptive) summaries
of the research. To this end, they are usually written in the fi nal stages of the
writing process. After completing this chapter, you should be able to do the
following:
■
Write a concise and informative abstract
■
Write a concise and informative title
As you work through the chapter, you will write an abstract and title for your own
paper. The Writing on Your Own tasks throughout the chapter will guide you
step by step as you do the following:
7A Read titles and abstracts
7B Prepare to write
7C Write your abstract
7D Write your title
7E Practice peer review
7F Fine-tune your abstract and title
When compared to the Introduction, Methods, Results, and Discussion sections
of a journal article, the title and abstract are quite short; the title usually has fewer
than 20 words, and many journals limit the abstract to fewer than 200 words.
Despite their brevity (and perhaps because of it), the title and abstract are the
most widely read sections of the journal article and thus are viewed by many as
the most important sections of the journal article.
An Important 200 Words
Titles and abstracts are read by more readers than any other section of the journal article.
Reading and Analyzing Writing
We begin by asking you to read and analyze the title and abstract for the aldehydes-in-beer article (excerpt 7A). The questions in exercise 7.1 will guide your
analysis of this excerpt.
Abstract
Concise and highly informative, the abstract informs readers about the purpose,
the theoretical or experimental approach, principal results, and major conclusions
of the work.
Exercise 7.1
As you read the title and abstract in excerpt 7A, consider the following:
a. Read the title. Which of the following are included: research topic, importance, gap statement, procedures, instrumentation, results, interpretations,
citations, conclusions?
b. The abstract contains six sentences (107 words). Briefly state the purpose of
each sentence. Based on these purposes, propose a move structure for the
abstract.
c. Are there any sentences in the abstract that do not include science content?
Explain.
d. Based only on the title and abstract, who are the intended audiences for
this article (including subdisciplines of chemistry)? Give reasons for your
choices.
242
The Journal Article
e. What rules do the authors follow regarding the use of abbreviations in their
abstract? What other writing conventions do you notice?
f. What verb tense(s) do the authors use in their abstract?
g. Suggest why the authors include keywords at the end of the abstract. How
many of these keywords also appear in the title and abstract?
Abstract Headings and Word Counts
In this chapter, we begin each abstract with a heading (Abstract) and conclude each
abstract with a word count. We do this for instructional purposes; headings and word
counts do not typically appear in published abstracts.
Excerpt 7A (from Vesely et al., 2003)
Abstract
Analysis of Aldehydes in Beer Using Solid-Phase Microextraction with On-Fiber
Derivatization and Gas Chromatography/Mass Spectrometry.
A new, fast, sensitive, and solventless extraction technique was developed in order to
analyze beer carbonyl compounds. The method was based on solid-phase microextraction with on-fiber derivatization. A derivatization agent, O-(2,3,4,5,6-pentafluorobenzyl)
hydroxylamine (PFBOA), was absorbed onto a divinyl benzene/poly(dimethylsiloxane)
65-μm fiber and exposed to the headspace of a vial with a beer sample. Carbonyl
compounds selectively reacted with PFBOA, and the oximes formed were desorbed into
a gas chromatograph injection port and quantified by mass spectrometry. This method
provided very high reproducibility and linearity. When it was used for the analysis of
aged beers, nine aldehydes were detected: 2-methylpropanal, 2-methylbutanal,
3-methylbutanal, pentanal, hexanal, furfural, methional, phenylacetaldehyde, and
(E)-2-nonenal. (107 words)
Keywords: Aldehydes; beer analysis; derivatization; SPME; GC/MS
7A Writing on Your Own: Read Titles and Abstracts
Read and review the titles and abstracts of the journal articles that you collected during
your literature search (started in chapter 2). How well do they capture the purpose, principal results, and conclusions of the work?
Use these titles and abstracts as models in your own writing.
Writing the Abstract and Title
243
Analyzing Audience and Purpose
Abstracts and titles are generally written for expert and scientific audiences; however, parts of each are also typically accessible to a student audience. For example,
the abstract in the aldehydes-in-beer article targets professional food chemists
and analytical chemists specifically, but a student in organic chemistry could read
the abstract and understand which aldehydes are present in aged beer. Moreover,
the student could also discern from the title that the article is about aldehydes
in beer.
The major purpose of the title is to inform readers about the specific content
of the work, ideally identifying both what was studied and how it was studied.
The major purpose of an abstract is to summarize, in one clear and concise paragraph, the purpose, experimental approach, principal results, and major conclusions of the work. In most journals, the abstract includes only text; in some
journals (e.g., The Journal of Organic Chemistry and Organic Letters), the abstract
also includes a graphic. Importantly, both the abstract and title must be able to
stand on their own. This is because these two sections (and only these two sections) are reprinted by abstracting services (e.g., Chemical Abstracts Service, or
CAS) in separate documents for literature searches. Also, many chemists read
titles and abstracts to obtain a quick overview of the journal’s contents but do not
read the articles in full.
CAS
The Chemical Abstracts Service (CAS) reprints titles and abstracts from refereed journal
articles to facilitate searches of the chemical literature.
As you may have noticed in excerpt 7A, some abstracts also include a list of
keywords. Keywords, required in many journals, help readers locate relevant
works when they search the literature. Guidance in selecting keywords is provided in Information for Authors documentation for journals that require them.
Even if the journal that you are targeting does not require keywords, it is wise to
create a list anyway and incorporate as many of these words as possible into your
title and abstract. Doing so will greatly increase the probability that your paper
will be found by interested individuals searching the literature.
Keywords
Searchable words that help scientists find relevant works. Keywords are often required in
abstracts. Some journals provide a list of keywords for authors to choose from.
244
The Journal Article
Analyzing Organization
We consider the organization for both the abstract and title. Because the abstract
is generally written before the title, we begin with the abstract.
The Abstract
The abstract involves three essential moves (figure 7.1). The major objectives of
these moves are to state (1) what was done, (2) how it was done, and (3) what
was found. Each move is designed to inform, not describe. The first move has
one required submove (submove 1.3): state purpose and/or accomplishment(s)
of work. In some cases, authors lead up to this submove by first identifying the
research area and its importance (submove 1.1) and/or a gap in the field that is
addressed by the work (submove 1.2), similar to moves 1 and 2 of the Introduction
section (see figure 6.1).
Move 2 summarizes the research methods; procedures and/or instrumental techniques may also be identified. The amount of detail presented varies
with the goals of the paper. A paper that describes the development of a novel
approach is likely to include more information than one that uses standard
1. State What Was Done
1.1 Identify the research area and its importance (optional)
1.2 Mention a gap addressed by the work (optional)
1.3 State purpose and/or accomplishment(s) of work
2. Identify Methods Used
(i.e., procedures and/or instrumentation)
3. Report Principal Findings
3.1 Highlight major results (quantitatively or qualitatively)
3.2 Offer a concluding remark (optional)
Figure 7.1 A visual representation of the move structure for a typical
journal article abstract.
Writing the Abstract and Title
245
methodologies. In articles that describe chemical syntheses, this move usually
includes a graphic.
Move 3 highlights the principal findings of the work and is often the longest
segment of the abstract. When practical, numerical values (with their error terms,
e.g., standard errors or deviations) are reported; otherwise, only the major trends
suggested by the data are summarized. It is not appropriate to include a table
in the abstract or to repeat all of the results presented in the paper. In many
instances, the abstract ends with a concluding statement that draws attention to
the major findings or impacts of the work.
The moves and submoves of the abstract directly parallel moves found in
other sections of the journal article. Despite these similarities, it is important
that you do not repeat yourself in the abstract. Effective writers resist the temptation to simply copy sentences from other sections of their papers to use in their
abstracts.
The Title
The title also has an organizational structure. After analyzing more than
300 titles of chemistry journal articles, we found that titles commonly follow
an “X of Y by Z” pattern (table 7.1). In essence, X, Y, and Z are three moves
linked together by common words (e.g., of or by). Y describes what was studied;
X and Z modify or extend Y in some way. Y is required; X and Z are optional,
but typically at least X or Z is present. Of course, this pattern illustrates only
a conventional way to construct a journal article title; countless variations are
possible.
Table 7.1 Common examples of the “X of Y by Z” pattern found in journal article titles.
X (optional)
Y (required)
Z (optional)
Basic Pattern
A nominalization
of
(e.g., Determination,
What was studied
on
Target of Y or what was
in
in
impacted by Y
Investigation, Analysis
for
via
Measurement)
to
by
Method used (or detail of
...
using
method used) to study Y
A phrase that refers to,
at
describes, or modifies Y
from
...
continued
246
The Journal Article
Table 7.1 (continued)
X (optional)
Y (required)
Z (optional)
Examples
Preparation
of
5-Substituted
1H-Tetrazoles
from
Nitriles in Watera
Analysis
of
Aldehydes in Beer
Using
Solid-Phase
Microextraction
with On-Fiber
Derivatization and
Gas Chromatography/
Mass Spectrometryb
Crystal Structure
of
Native Chicken
Fibrinogen
at
2.7 Å Resolutionc
Heteronuclear
Recoupling
in
Solid-State MagicAngle-Spinning
NMR
via
Overtone Irradiationd
Cancer-Protective
Properties
of
High-Selenium
Broccolie
A Class II Aldolase
Mimicf
a. Demko and Sharpless (2001).
b. Vesely et al. (2003).
c. Yang et al. (2001).
d. Wi and Frydman (2001).
e. Finley et al. (2001).
f. Hedin-Dahlström et al. (2006).
Exercise 7.2
Consider the following 10 titles. Do they conform to the pattern presented in
table 7.1? When possible, identify X, Y, and Z in each title.
a. Effect of Randomly Methylated -Cyclodextrin on Physical Properties of Soils
(from Jozefaciuk et al., 2003)
b. Determination of Polychlorinated Biphenyls in Milk Samples by
Saponification—Solid-Phase Microextraction (from Llompart et al., 2001)
c. Role of Free Radicals in the Toxicity of Airborne Fine Particulate Matter (from
Dellinger et al., 2001)
d. Antioxidative Activity of Volatile Chemicals Extracted from Beer (from
Wei et al., 2001)
e. Antiadhesive Effect of Green and Roasted Coffee on Streptococcus mutans’
Adhesive Properties on Saliva-Coated Hydroxyapatite Beads (from Daglia
et al., 2002)
Writing the Abstract and Title
247
f. Biotransformation and Accumulation of Arsenic in Soil Amended with
Seaweed (from Castlehouse et al., 2003)
g. In Vitro Effect of Arsenical Compounds on Glutathione-Related Enzymes
(from Chouchane and Snow, 2001)
h. Chemical Characterization of Sicilian Prickly Pear (Opuntia ficus indica) and
Perspectives for the Storage of Its Juice (from Gurrieri et al., 2000)
i. A Method for the Analysis of Low-Mass Molecules by MALDI-TOF Mass
Spectrometry (from Guo et al., 2002)
j. Arsenic Contamination of Bangladesh Paddy Field Soils: Implications for Rice
Contribution to Arsenic Consumption (from Meharg and Rahman, 2003)
7B Writing on Your Own: Prepare to Write
Before you begin writing your own abstract and title, make a list of keywords that
another researcher might use to find your paper in a literature search. (You should
incorporate many of these words in your abstract and title.)
Determine the word limit for the abstract that you are writing. Do not surpass
this word limit.
Review the move structure for the abstract (figure 7.1). Outline the information
that you want to include in each move of your abstract.
Analyzing Abstracts
In this section, we read and analyze abstracts taken from chemistry journal articles. (Later in the chapter, we focus on titles.) We include passages from abstracts
(P1–P17) and entire abstracts (excerpts 7B–7H) to illustrate both individual
moves and how abstract moves work together as a whole. In part 1, we examine
selections move by move. Because abstracts in organic chemistry journals vary
slightly from other chemistry journals, we consider them separately at the end of
part 1. In part 2, we examine writing practices that span the entire abstract.
Part 1: Analyzing Excerpts
Move 1: State What Was Done
Recall that the first move of the abstract has two optional submoves (1.1 and 1.2)
and one required submove (1.3). We begin by examining four passages from
abstracts that begin immediately with the required submove. Each example is the
248
The Journal Article
first sentence of the abstract. The purpose of this required submove is to state the
major purpose or accomplishments of the work. Note that the words used in this
submove must be different than the words used in move 3 of the Introduction
section, which introduces the reader to the current work.
P1 Antioxidative compounds were isolated from the 50% methanol extract
of dried leaves of Celastrus hindsii. (From Ly et al., 2006)
P2 In this study, we report the chemical synthesis and functionalization of
magnetic and gold-coated magnetic nanoparticles and the immobilization
of single-stranded biotinylated oligonucleotides onto these particles. (From
Kouassi and Irudayaraj, 2006)
P3 Hydrogen (H2) concentrations during reductive dechlorination of cisdichloroethene (cDCE) and vinyl chloride (VC) were investigated with
respect to the influence of parameters entering the Gibbs free energy
expression of the reactions. (From Heimann and Jakobsen, 2006)
P4 A method for analyzing ergosterol in a single kernel and ground barley
and wheat was developed using gas chromatography-mass spectrometry
(GC-MS). (From Dong et al., 2006)
We next examine passages from abstracts that begin with a description of
the general research area and/or mention a gap in the field (optional submoves 1.1
and 1.2). In these passages (P5–P7), we include not only the first sentence but
several additional sentences to show how the authors lead up to submove 1.3.
Note that although others’ works are alluded to in these passages, no citations
are included. This absence of citations is true not only here but throughout
the abstract. If a work must be cited in an abstract (a rare occurrence), the full
citation must be included in the abstract; in this way, the abstract can stand
alone.
Cite in an Abstract?
In general, most journals prefer that you not cite others’ works in the abstract.
P5 Studies have shown that ebselen is an antiinflammatory and
antioxidative agent. Its protective effect has been investigated in
oxidative stress related diseases such as cerebral ischemia in recent
years. However, experimental evidence also shows that ebselen
causes cell death in several different cell types. Whether ebselen will
have a beneficial or detrimental effect on cells under ischemic
condition is not known. Herein, we studied the effect of ebselen
Writing the Abstract and Title
249
on C6 glioma cells under oxygen and glucose deprivation (OGD), an in
vitro ischemic model. (From Shi et al., 2006)
Affect vs. Effect
See appendix A for more information on these easily confused words.
P6 Atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino]-1,3,5-triazine)
is one of the most commonly used herbicides in North America and
is frequently detected in ground and surface waters. This research
investigated possible covalent modifications of hemoglobin following
in vivo exposures to atrazine in Sprague Dawley (SD) rats and in vitro
incubations with diaminochlorotriazine. (From Dooley et al., 2006)
P7 Over the past decade, electron monochromator-mass spectrometry
(EM-MS) has been shown to be a selective and sensitive technique for
the analysis of a wide variety of electrophilic compounds in complex
matrixes. Here, for the first time, three different dinitroaniline pesticides,
flumetralin, pendimethalin, and trifluralin, have been shown to be
present in both mainstream and sidestream tobacco smoke using an
EM-MS system. (From Dane et al., 2006)
Exercise 7.3
Identify submoves 1.1–1.3 in passages P5–P7. When appropriate, indicate which
submoves are absent.
Move 2: Identify Methods Used
The next several passages illustrate how experimental methods are reported in
abstracts. We begin with two passages that describe procedures: P8 highlights
steps taken to extract pesticides from cigarette smoke; P9 highlights steps taken
to separate proteins using novel forms of electrophoresis and chromatography.
Note that the authors of P9 define PMMA, the abbreviation for poly(methyl methacrylate), in the title of their paper; hence, it is used without definition in their
abstract. All other abbreviations are defined in P9.
Abbreviated Terms in Abstracts and Titles
Acronyms and abbreviations, used only to prevent needless repetition, should be defined
in the abstract (or title) so that the abstract, together with the title, can stand alone. These
250
The Journal Article
abbreviations should be defined again in the article. Common abbreviations (e.g., NMR)
need not be defined.
P8 A number of cigarettes were tested including three pure-tobacco-type
cigarettes, an experimental reference cigarette, and 11 commercial
cigarettes. Due to the complexity of the smoke particulate matter,
the pesticides were identified only after each sample was subjected
to a multistep cleanup process that included phenyl solid-phase
extraction, an acid wash, aminopropyl solid-phase extraction, and
normal phase liquid chromatography fractionation. (Adapted from
Dane et al., 2006)
P9 Sodium dodecyl sulfate microcapillary gel electrophoresis (SDS
μ-CGE) and micellar electrokinetic chromatography (MEKC) were
used as the separation modes for the first and second dimension of
the electrophoresis, respectively. The microchip was prepared by
hot embossing into PMMA from a brass mold master fabricated via
high-precision micromilling. The microchip incorporated a 30-mm
SDS μ-CGE and a 10-mm MEKC dimension length. Electrokinetic
injection and separation were used with field strengths of up to
400 V/cm. Alexa Fluor 633 conjugated proteins, ranging in size
from 38 to 110 kDa, were detected using laser-induced fluorescence
with excitation/emission at 633/652 nm. (From Shadpour and
Soper, 2006)
P10 and P11 illustrate how authors commonly refer to instrumentation in their
abstracts. In most cases, instrument names are written out in full (without acronyms), and no information regarding vendors, model numbers, or operational
parameters is included.
P10 Eight phenolic compounds . . . were . . . obtained by reversed-phase
high-performance liquid chromatography, and their structures were
elucidated by NMR spectroscopy and mass spectrometry analyses.
(Adapted from Ly et al., 2006)
P11 Particle size and oligonucleotide attachment were confirmed by
transmission electron microscopy; oligonucleotide binding was
characterized by Fourier transform infrared spectroscopy and
hybridization confirmed by fluorescence emission from the fluorophore
attached to the target oligonucleotide strand. The rate of hybridization
was measured using a spectrofluorometer and a microarray scanner.
(From Kouassi and Irudayaraj, 2006)
Writing the Abstract and Title
251
Move 3: Report Principal Findings
Move 3, the last and most important move of the abstract (and often the longest),
highlights the principal findings of the work. Three examples are considered
(P12–P14). Only the most essential or representative data are reported, including
numerical values, when appropriate. (Note that numerical data should include
units and standard errors or deviations. Do not omit units or error terms to conserve space.) Move 3 may also inform readers about the contents of the full article.
For example, P12 informs readers that acute toxicity information for three pesticides is presented in the text. Move 3 sometimes ends with a concluding remark.
In P12 and P13, the data themselves end the abstract and no summative remarks
are made; in P14, the authors add a concluding remark.
Error Terms
Error terms, such as standard deviations and standard errors, should be included in the
abstract, when appropriate.
The ACS Style Guide recommends including a space before and after the ““ symbol
(e.g., 17 9 mL).
P12 All cigarette types tested showed the presence of the three pesticides in
the tobacco smoke, with flumetralin ranging from trace levels up to 37
(9) ng/cig, pendimethalin ranging from trace levels up to 10.4 (0.6)
ng/cig, and trifluralin ranging from trace levels up to 47 (17) ng/cig.
Acute toxicity information is presented for the three pesticides. (From
Dane et al., 2006)
P13 [Note: The authors define ethyl vinyl ether (EVE), propyl vinyl ether
(PVE), and butyl vinyl ether (BVE) in the first part of the abstract.] . . .
Using a relative kinetic method, rate coefficients (in units of cm3
molecule–1 s –1) of 7.79 1.71 10 –11, 9.73 1.94 10 –11, and 1.13 0.31 10 –10 have been obtained for the reaction of OH with EVE, PVE,
and BVE, respectively; 1.40 0.35 10 –12, 1.85 0.53 10 –12, and
2.10 0.54 10 –12 for the reaction of NO3 with EVE, PVE, and BVE,
respectively; and 2.06 0.42 10 –16, 2.34 0.48 10 –16, and 2.59 0.52 10 –16 for the ozonolysis of EVE, PVE, and BVE, respectively.
Tropospheric lifetimes of EVE, PVE, and BVE with respect to the
reactions with reactive tropospheric species (OH, NO3 and O3)
have been estimated for typical OH and NO3 radical and ozone
concentrations. (Adapted from Zhou et al., 2006)
P14 The recoveries of ergosterol from ground barley were 96.6, 97.1, 97.1,
88.5, and 90.3% at the levels of 0.2, 1, 5, 10, and 20 μg/g (ppm),
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The Journal Article
respectively. The recoveries from a single kernel were between 93.0
and 95.9%. The precision (coefficient of variance) of the method was
in the range 0.8–12.3%. The method detection limit and the method
quantification limit were 18.5 and 55.6 ng/g (ppb), respectively. The
ergosterol analysis method developed can be used to handle 80 samples
daily by one person, making it suitable for screening cereal cultivars
for resistance to fungal infection. The ability for detecting low levels of
ergosterol in a single kernel provides a tool to investigate early fungal
invasion and to study mechanisms of resistance to fungal diseases.
(From Dong et al., 2006)
Respectively
See appendix A and chapter 4.
Major fi ndings may also be expressed in more qualitative, and less quantitative, terms by highlighting general trends in the abstract. Three examples
are provided below. P16 and P17 offer two additional examples of concluding
remarks.
P15 Variations in the temperature between 10 and 30 °C did not affect the
H 2 concentration in a fashion that suggested thermodynamic control
through a constant energy gain. In another set of experiments, H 2
levels at constant ionic strength were independent of the chloride
concentration between 10 and 110 mmol chloride per liter. These
fi ndings demonstrate that the partial equilibrium approach is not
directly applicable to the interpretation of reductive degradation of
chlorinated ethenes. We also present recalculated thermodynamic
properties of aqueous chlorinated ethene species that allow for
calculation of in situ Gibbs free energy of dechlorination reactions at
different temperatures. (From Heimann and Jakobsen, 2006)
P16 The rate of hybridization increased concomitantly with the
concentration of the probe and the target in the reaction medium.
Furthermore, exposure of probe and target oligonucleotide to a
combination of target and noncomplementary DNA strands reduced the
rate of hybridization, possibly because of steric crowding in the reaction
medium and cross-linking between reacting oligonucleotides and
the noncomplementary strands. The study undertaken opens several
possibilities in bioconjugate attachment to functionalized iron and iron
nanocomposite structures for controlled manipulation and handling
using magnetic fields. (From Kouassi and Irudayaraj, 2006)
Writing the Abstract and Title
253
P17 Oil from the T/V Exxon Valdez was found on 14 shorelines, mainly
in Herring Bay and Lower Pass, with an estimated 0.43 ha covered
by surface oil and 1.52 ha containing subsurface oil. Surface and
subsurface oil were most prevalent near the middle of the intertidal
and had nearly symmetrical distributions with respect to tide height.
Hence, about half the oil is in the biologically rich lower intertidal,
where predators may encounter it while disturbing sediments in search
of prey. The overall probability of encountering surface or subsurface oil
is estimated as 0.0048, which is only slightly greater than our estimated
probability of encountering subsurface oil in the lower intertidal of
Herring Bay or Lower Pass. These encounter probabilities are sufficient
to ensure that sea otters and ducks that routinely excavate sediments
while foraging within the intertidal would likely encounter subsurface
oil repeatedly during the course of a year. (From Short et al., 2006)
We end this section by examining two complete abstracts from two journals in
organic chemistry: The Journal of Organic Chemistry and Organic Letters. Both journals require authors to include a graphic in their abstracts. This graphic appears
in the abstract and in the journal’s table of contents, along with the title. The
graphic is often a reaction mechanism or scheme described in the article but
may also be an illustrative sketch, graph, or spectrum. The graphic has no title
or caption but may include text for labeling purposes (i.e., to label compounds, R
groups, reaction arrows, etc.). Color is allowed in the abstract graphic.
Excerpt 7B is from The Journal of Organic Chemistry. For the most part, this
abstract follows the move structure presented in figure 7.1: the opening sentence
describes accomplishments, the second sentence identifies methods, the third
and fourth sentences summarize key results, and the last sentence offers a conclusion. Notice, however, that no information is given about the synthetic procedure
because this information is contained in the graphic.
Excerpt 7B (from Hedin-Dahlström et al., 2006)
Abstract
O
H
+
O
MIP
H
O
1a
2
3a
A class II aldolase-mimicking synthetic polymer was prepared by the molecular imprinting
of a complex of cobalt (II) ion and either (1S,3S,4S)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]
heptan-2-one (4a) or (1R,3R,4R)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4b)
254
The Journal Article
in a 4-vinylpyridine-styrene-divinylbenzene copolymer. Evidence for the formation of
interactions between the functional monomer and the template was obtained from
NMR and UV–vis titration studies. The polymers imprinted with the template demonstrated enantioselective recognition of the corresponding template structure, and
induced a 55-fold enhancement of the rate of reaction of camphor (1) with benzaldehyde
(2), relative to the solution reactions, and were also compared to reactions with a series
of reference polymers. Substrate chirality was observed to influence reaction rate, and
the reaction could be competitively inhibited by dibenzoylmethane (6). Collectively,
the results presented provide the fi rst example of the use of enantioselective
molecularly imprinted polymers for the catalysis of carbon–carbon bond formation.
(139 words)
Compound Labels
Compound labels are common in abstracts. They should follow the numbering scheme
used in the main text. (See chapter 4 and appendix A.)
Excerpt 7C is the abstract from Boesten et al. (2001), one of the six key articles
referred to throughout this module. The article is published in Organic Letters,
which limits abstracts to no more than 75 words. This particular abstract contains 67 words and only three sentences. The first sentence accomplishes move 1,
the second sentence (with the graphic) addresses moves 2 and 3, and the last
sentence accomplishes move 3. Quite concise, don’t you agree?
Excerpt 7C (adapted from Boesten et al., 2001)
Abstract
Ph
a) R1R2CO
Ph
H2N
HN
(in situ)
CONH2
b) NaCN, AcOH
solvent, time, temp
R1
Ph
CONH2
CN
HN
+
R1
R2
CONH2
CN
R2
76–93% yield, dr >99/1
Ph
NH2
HN
H
CONH2
CN
3 steps
H
COOH
73% yield, >98% ee
Diastereoselective Strecker reactions based on (R)-phenylglycine amide as chiral auxiliary are reported. The Strecker reaction is accompanied by an in situ crystallizationinduced asymmetric transformation, whereby one diastereomer selectively precipitates and
Writing the Abstract and Title
255
can be isolated in 76–93% yield and dr 99/1. The diastereomerically pure -amino
nitrile obtained from pivaldehyde (R1 t-Bu, R 2 H) was converted in three steps to
(S)-tert-leucine in 73% yield and 98% ee. (67 words)
Exercise 7.4
Excerpt 7D, the abstract from Demko and Sharpless (2001) on the synthesis
of substituted tetrazoles, is quite concise: two sentences and 57 words! Read
excerpt 7D and determine if all of the moves are present. In addition, answer
these questions:
a. What move(s) or submove(s) is accomplished in the graphic?
b. What move(s) or submove(s) is accomplished in the text of the abstract?
c. What results do you expect to find in the full text?
d. Do the authors present their results quantitatively or qualitatively?
e. Do the authors include a summative remark?
f. How do the authors use verb tenses?
Excerpt 7D (from Demko and Sharpless, 2001)
Abstract
1.1 equiv NaN3
R
C
N
1.0 equiv ZnBr2
N
R
water
reflux
NH
N
N
R = Ar, Alk, Vinyl, SR, NR2
The addition of sodium azide to nitriles to give 1H-tetrazoles is shown to proceed readily
in water with zinc salts as catalysts. The scope of the reaction is quite broad; a variety of
aromatic nitriles, activated and unactivated alkyl nitriles, substituted vinyl nitriles, thiocyanates, and cyanamides have all been shown to be viable substrates for this reaction.
Part 2: Analyzing Writing across the Abstract
In this section, we summarize writing practices that span the entire abstract. Some
of these have been mentioned previously but are repeated here for convenience.
■
256
Abbreviations and acronyms: The ACS Style Guide suggests that writers use
abbreviated terms sparingly in abstracts; they should be used mainly to
The Journal Article
minimize awkwardness and needless repetition. When abbreviated terms
are used in the abstract, they should be defined at first use (unless they are
too common to require definition). For those that are defined, they must be
defined again at their first mention in the paper.
■
Citations: The ACS Style Guide states that references should not be cited in the
abstract. If a citation cannot be avoided, the full reference must be included
so that the abstract may stand on its own.
■
Error terms and units: If data are presented quantitatively in the abstract,
proper units and errors terms (when appropriate) should be included.
■
Formatting: If you glance through several different chemistry journals, you
will notice that abstracts are easily identifiable; they are often set apart in
some way from the body of the paper by using a different font, margins,
or spacing. However, you need not (and should not) attempt to “copy” the
formatting that you see in published works as you prepare your manuscript. Unless otherwise stated, the abstract should be double spaced and
in the same font as the rest of the manuscript. Typically the first page of
the submitted manuscript comprises the title, author list, and abstract; the
Introduction section begins on the second page. If your paper is accepted, the
journal editors may give you additional formatting instructions to prepare for
publication.
■
Keywords: The repetition of key terms and concepts in the abstract
and title is commonplace. Because both the title and abstract are often
used for computer searches, it is important that key terms be included
in both.
■
Vendors: Instrumentation is identified in the abstract but not vendors or
brand names.
■
Verb tenses: Verb tenses in the abstract are consistent with conventions used
in other sections of the journal article. Past tense is used to refer to work
completed in the past and to describe results:
Past tense
Antioxidative compounds were isolated.
A number of cigarettes were tested.
All cigarette types tested showed the presence of . . .
Present tense is used to make statements of fact, to identify information
reported in the paper, and to state beliefs or interpretations expected to be
true over time:
Present tense
Atrazine is a commonly used herbicide.
Diastereoselective Strecker reactions are reported.
The results provide the first example of . . .
The study undertaken opens several possibilities.
Writing the Abstract and Title
257
Present perfect can be used to summarize the work of others, demonstrate a
gap, introduce one’s own work, and/or report principal findings:
Present perfect
Studies have shown that . . .
. . . in vivo toxicity has not yet been proved.
Here, for the first time, three different dinitroaniline pesticides have been
shown . . .
■
Voice. Both passive and active voice are used in abstracts, although passive
voice is more common:
Passive voice (more common)
Although cyclodextrins are used in soil decontamination . . .
The effects of RAMEB concentrations on clay minerals were studied . . .
A saponification-HSSPME procedure has been developed . . .
Active voice (less common)
The scope of the reaction is quite broad.
Variations in temperature did not affect . . .
The results provide the first examples . . .
■
We. The word we is used only rarely in abstracts; when used, it usually refers
to work that the authors present in the paper:
We report the chemical synthesis of . . .
We present calculated thermodynamic values for . . .
Present Perfect
See table 6.2.
Tense–Voice Combinations
See tables 4.1, 5.1, and 6.5.
Exercise 7.5
Read excerpts 7E–7H (abstracts from four articles examined in chapters 3–6).
a. Consult figure 7.1. Which moves and submoves are accomplished within the
first two sentences of each abstract?
b. Find at least two examples in these abstracts that support and/or refute each
general writing practice listed in part 2 (excluding error terms, formatting,
and keywords).
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c. Excerpts 7E–7H were published in journals that do not require keywords.
Using the abstracts and titles as guides, suggest three keywords for each
abstract.
d. Which excerpt ends with a concluding remark that goes beyond reporting
results?
Excerpt 7E (from Jozefaciuk et al., 2001)
Abstract
Although cyclodextrins are increasingly used in soil decontamination, little is known
about their effects on soil physicochemical properties. In this work, the surface and
pore properties of randomly methylated -cyclodextrin (RAMEB) and three typical
clay minerals were characterized, and the effects of RAMEB concentrations on clay
minerals were studied using water vapor adsorption-desorption and mercury intrusion porosimetry techniques. As compared to clay minerals, for pure RAMEB, very
large surface area and volume of nanometer-size pores (micropores) were determined.
Energy of interaction with water vapor, volume of micrometer-size pores (mesopores),
and fractal dimensions in both pore size ranges of RAMEB were lower than those of
the minerals. When increasing amounts of RAMEB were added to the minerals, the
surface area and micropore volume decreased and adsorption energy increased. The
volume of mesopores decreased after RAMEB treatments for bentonite and kaolin
and increased for illite. As deduced from the fractal dimensions increase, the pore
structure of the minerals became more complex with RAMEB addition. The observed
changes were in general contrary to those expected when RAMEB and minerals coexist as separate, nonreactive phases and suggested strong interaction of RAMEB with
clay minerals. (190 words)
Excerpt 7F (from Llompart et al., 2001)
Abstract
A saponification-HSSPME procedure has been developed for the extraction of PCBs
from milk samples. Saponification of the samples improves the PCB extraction efficiency and allows attaining lower background. A mixed-level fractional design has
been used to optimize the sample preparation process. Five variables have been considered: extraction time, agitation, kind of microextraction fiber, concentration, and
volume of NaOH aqueous solution. Also the kinetics of the process has been studied
with the two fibers (100-μm PDMS and 65-μm PDMS-DVB) included in this study.
Analyses were performed on a gas chromatograph equipped with an electron capture
detector and a gas chromatograph coupled to a mass selective detector working in
MS-MS mode. The proposed method is simple and rapid, and yields high sensitivity,
with detection limits below 1 ng/mL, good linearity, and reproducibility. The method
has been applied to liquid milk samples with different fat content covering the whole
Writing the Abstract and Title
259
commercial range, and it has been validated with powdered milk certified reference
material. (159 words)
Excerpt 7G (adapted from Dellinger et al., 2001)
Abstract
Exposure to airborne fine particles (PM 2.5) is implicated in excess of 50 000 yearly
deaths in the USA as well as a number of chronic respiratory illnesses. Despite intense
interest in the toxicity of PM 2.5, the mechanisms by which it causes illnesses are poorly
understood. Because the principal source of airborne fine particles is combustion and
combustion sources generate free radicals, we suspected that PM 2.5 may contain radicals. Using electron paramagnetic resonance (EPR), we examined samples of PM2.5 and
found large quantities of radicals with characteristics similar to semiquinone radicals.
Semiquinone radicals are known to undergo redox cycling and ultimately produce
biologically damaging hydroxyl radicals. Aqueous extracts of PM 2.5 samples induced
damage to DNA in human cells and supercoiled phage DNA. PM 2.5-mediated DNA
damage was abolished by superoxide dismutase, catalase, and deferoxamine, implicating
superoxide radical, hydrogen peroxide, and the hydroxyl radical in the reactions inducing DNA damage. (147 words)
Excerpt 7H (from Plaper et al., 2002)
Abstract
Trivalent chromium is a metal required for proper sugar and fat metabolism. However, it
has been suggested that it causes DNA damage in in vitro test systems, although in vivo
toxicity has not yet been proved. In the present study, the effect of Cr3 on bacterial cells
was tested with the Pro-Tox (C) assay, and its cellular uptake was measured with fl ame
atomic absorption spectroscopy. The potential genotoxicity of Cr3 was further examined by the study of its influence on a bacterial type II topoisomerase. Cr3 was shown
to cause DNA damage and inhibit topoisomerase DNA relaxation activity, probably by
preventing the formation of the covalent link between enzyme and double helix. In
addition, Cr3 decreases the viability and/or proliferation rate of eukaryotic cells such as
murine B16 melanoma cells and human MCF-10A neoT ras-transformed human epithelial cells. The possible implication for Cr3 intake by humans is discussed. (148 words)
Exercise 7.6
Below is an abstract from the literature (adapted from Cortes et al., 2006). The
text has been divided into four passages and their order scrambled. Based on the
move structure in figure 7.1, suggest the correct order for passages a–d.
a. Pesticide residues were extracted from samples with a small amount of ethyl
acetate and anhydrous sodium sulfate. No additional concentration and
cleanup steps were necessary. Analyses were performed by large volume GC
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injection using the through oven transfer adsorption desorption (TOTAD)
interface.
b. A simple, rapid, and sensitive multiresidue method has been developed for
the determination in vegetables of organophosphorus pesticides commonly
used in crop protection.
c. Results are reported for the analyses of eggplant, lettuce, pepper, cucumber,
and tomato.
d. The calculated limits of detection for each pesticide injecting 50 μL of extract
and using an NPD were lower than 0.35 μg/kg, which is much lower than
the maximum residues levels (MRLs) established by European legislation.
Repeatability studies yielded a relative standard deviation lower than 10% in
all cases.
Exercise 7.7
The following abstract (adapted from Hageman et al., 2006) has been determined
to be too long by its authors (221 words). The authors would like to reduce it to
fewer than 200 words and, if possible, to 185 words. Rewrite the abstract to make
it more concise.
Abstract
The United States National Park Service has initiated an extensive research campaign on the atmospheric deposition and fate of semi-volatile organic compounds
in its alpine, sub-Arctic, and Arctic ecosystems in the Western U.S. Results of the
analyses of pesticides in seasonal snowpack samples collected in spring 2003 from
seven national parks are presented in the Results section of this paper. From a target
analyte list of 47 pesticides and degradation products, the most frequently detected
current-use pesticides were dacthal, chlorpyrifos, endosulfan, and -hexachlorocyclohexane, whereas the most frequently detected historic-use pesticides were dieldrin,
-hexachlorocyclohexane, chlordane, and hexachlorobenzene. The results of several
tests are described in this paper to help to explain what sources are responsible for
our pesticide results. Correlation analysis with latitude, temperature, elevation, particulate matter, and two indicators of regional pesticide use reveals that regional
current and historic agricultural practices are largely responsible for the distribution
of pesticides in the national parks in this study. Pesticide deposition in the Alaskan
parks is attributed to long-range transport because there are no significant regional
pesticide sources. The percentage of total pesticide concentration due to regional
transport (%RT) was calculated for the other parks; %RT was highest at parks with
higher regional cropland intensity and for pesticides with lower vapor pressures
and shorter half-lives in air. These results have many important implications.
(222 words)
Writing the Abstract and Title
261
7C Writing on Your Own: Write Your Abstract
Using figure 7.1 and the abstracts that you have collected from the literature as guides,
write each part of your abstract. Remember to use keywords and to make your text concise
and informative rather than descriptive. Include units and error bars when appropriate.
Abide by the word limit specified by your targeted journal.
Analyzing Titles
We conclude this chapter and module with a brief look at titles, often the last
part of a journal article to be written. The title of a journal article must be as
concise, specific, and informative as possible. Also, because the title is written for
an expert audience, the title should be formal. Although an informal, catchy title
is appropriate in many genres (e.g., in newspaper headlines and popular science
articles), it is inappropriate in a journal article.
A common organizational pattern for titles (X of Y by Z) was presented in table 7.1.
According to this pattern, titles often begin with a nominalization or phrase (X)
that modifies what was studied (Y). Avoid preceding X with empty words (e.g.,
“The,” “A,” “An”) or redundant phrases (e.g., “A Study of,” “Research on”); such
redundancy will make your title wordy, without adding relevant information.
Wordy The Preparation of 5-Substituted 1H-Tetrazoles . . .
A Study of the Cancer-Protective Properties of . . .
An Analysis of Aldehydes in Beer Using . . .
Better
Preparation of 5-Substituted 1H-Tetrazoles . . .
Cancer-Protective Properties of . . .
Analysis of Aldehydes in Beer Using . . .
Capitalization in Titles
Capitalize all main words (nouns, pronouns, verbs, adjectives, and adverbs).
Do not capitalize prepositions or the following words (unless they are used as the very
first word in a title):
a
and
nor
so
an
but
or
the
See appendix A for more on capitalization.
262
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Two- and three-word modifiers (often requiring the use of hyphens) are common in titles because they can make the title more concise. The hyphenated words
may be used in the X, Y, and/or Z parts of the title, as illustrated below. (Note, too,
that none of these titles begin with the word “The.”)
X
Continuous-Flow pI-Based Sorting of Proteins and Peptides in a
Microfluidic Chip Using Diffusion Potential (from Song, Y.-A.,
et al., 2006)
X, Y Synthesis and Self-Assembling Properties of Diacetylene-Containing
Glycolipids (from Nie and Wang, 2006)
Y
Atmospheric Deposition of Current-Use and Historic-Use Pesticides in
Snow at National Parks in the Western United States (from Hageman
et al., 2006)
Y
Comparison of Odor-Active Volatile Compounds of Fresh and Smoked
Salmon (from Varlet et al., 2006)
Y
Inhibition of Hemoglobin- and Iron-Promoted Oxidation in Fish
Microsomes by Natural Phenolics (from Pazos et al., 2006)
Z
Sampling and Determination of Formaldehyde Using Solid-Phase
Microextraction with On-Fiber Derivatization (from Martos and
Pawliszyn, 1998)
Z
Determination of Polychlorinated Biphenyls in Milk Samples by
Saponification—Solid-Phase Microextraction (from Llompart
et al., 2001)
Two-Word Modifiers
See appendix A.
Colons are also common in titles. If you use colons, be sure that the segment of
the title that precedes the colon can stand alone as the full title. The passage after
the colon may or may not stand alone. It is customary to capitalize the first word
after the colon, as if it were the start of a new sentence. Here are a few examples:
A Simple and Rapid Assay for Analyzing Residues of Carbamate Insecticides
in Vegetables and Fruits: Hot Water Extraction Followed by Liquid
Chromatography-Mass Spectrometry (from Bogialli et al., 2004)
Arsenic Contamination of Bangladesh Paddy Field Soils: Implications for Rice
Contribution to Arsenic Consumption (from Meharg and Rahman, 2003)
Effect of Six Decades of Selective Breeding on Soybean Protein Composition
and Quality: A Biochemical and Molecular Analysis (from Mahmoud
et al., 2006)
Writing the Abstract and Title
263
Accurate Inertias for Large-Amplitude Motions: Improvements on Prevailing
Approximations (from Wong et al., 2006)
To make your title informative, be as specific as possible and avoid words that do
not convey the specific content of your study. Also, remember to use keywords
in your title. Because keywords promote effective literature retrieval, they should
be used liberally in the title. In the following examples, words that were listed as
keywords in the abstract are italicized.
Noncovalent Cross-Linking of Casein by Epigallocatechin Gallate Characterized
by Single Molecule Force Microscopy (from Jöbstl et al., 2006)
Factors Affecting Transfer of Polycyclic Aromatic Hydrocarbons from Made Tea
to Tea Infusion (from Lin et al., 2006)
Herbicidal Effects of Soil-Incorporated Wheat (from Mathiassen et al., 2006)
The ACS Style Guide recommends that authors spell out most terms in titles
(except for common abbreviations, e.g., NMR, DNA, and UV). Some journals
allow a few additional terms to be used in titles without definition (e.g., FTIR,
PCBs, GC/MS, and PAHs). In the following examples, NMR, GC/MS, and PCB
are not defined; PAH is defined in one title but not in two others, and MDAM is
defined.
Monofluorinated Analogues of Polybrominated Diphenyl Ethers as Analytical
Standards: Synthesis, NMR, and GC-MS Characterization and Molecular
Orbital Studies (from Luthe et al., 2006)
Atmospheric PCB Concentrations at Terra Nova Bay, Antarctica (from
Gambaro et al., 2005)
Biodegradation, Bioaccessibility, and Genotoxicity of Diffuse Polycyclic
Aromatic Hydrocarbon (PAH) Pollution at a Motorway Site (from Johnsen
et al., 2006)
Molecular Simulations of Benzene and PAH Interactions with Soot (from
Kubicki, 2006)
Application of Multi-Component Damage Assessment Model (MDAM)
for the Toxicity of Metabolized PAH in Hyalella azteca (from Lee and
Landrum, 2006)
When in Doubt about Abbreviations
If you are unsure about abbreviations in your title or abstract, search for keywords and
abbreviations in published abstracts using the ACS Journals Search. In this way, you can
determine common practices in your target journal.
264
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Exercise 7.8
Rewrite the following titles so that they better conform to the writing guidelines
presented in the chapter.
a. A Study Of How Fermentation and Distillation affect the Oxygen-18/
Oxygen-16 Isotope Ratio in Ethanol
b. Are There Chlorogenic Acids and Lactones in Your Caffeinated and
Decaffeinated Coffees? HPLC-MS has the Answer
c. Tree Bark: An Analysis of How Brominated Flame Retardants Impact Tree
Bark in North America
Exercise 7.9
Using only the information provided, propose titles for the following journal
articles. Use the X of Y by Z pattern, whenever possible.
a. A paper that reports the antioxidant activity of the phenolic fraction in extra
virgin olive oil (EVOO) using electrochemical methods
b. A paper that describes a novel method used to synthesize quinolines by incorporating allenyl cations in a catalytic intermolecular Friedel–Crafts reaction
c. A paper that describes the results of an inhalation study using Sprague–
Dawley rats to investigate the toxicity of low levels of 1,3-butadiene
7D Writing on Your Own: Write Your Title
Identify keywords to include in your title. Then, using table 7.1 as a guide, write a title for
your paper, making every attempt to follow the X of Y by Z pattern. Make sure that your
title is concise, specific, and informative.
Consider your use of capitalization, colons, and abbreviations. Do they follow recommended guidelines and/or common practices, as seen in others’ titles?
Reread your title. Does it capture the essence of your paper, including content and
emphases? Have you incorporated keywords in the title?
7E Writing on Your Own: Practice Peer Review
Imagine that a friend has asked you to review an abstract and title that are in draft form
(see “Peer Review Practice: Title and Abstract” at the end of the chapter for instructions,
background information, and the draft). Based on what you have learned in this chapter,
read the draft and offer written feedback.
Writing the Abstract and Title
265
7F Writing on Your Own: Fine-Tune Your Abstract and Title
After practicing the peer review process with the abstract and title at the end of the chapter, solicit feedback on your own abstract and title from a peer.
Use the Peer Review Memo on the Write Like a Chemist Web site to exchange feedback.
Use the feedback received to make final changes in your work.
After those changes are made, you will be ready to complete your journal article so that
it reads as a single, unified document (with all its essential components, including the title
and abstract, Introduction, Methods, Results, and Discussion sections, and references). See
chapter 17 for details on formatting references and chapter 18 for hints on finalizing your
written work.
Congratulations! You’ve just about completed your journal article.
Finalizing Your Written Work
See chapters 17 and 18.
Chapter Review
As a self-test, check what you’ve learned in this chapter by explaining the purpose and characteristics of each of the following terms to a friend who is new to
the field:
abstract
keywords
CAS
title
Also explain the following to a friend in chemistry who has not yet given much
thought to the final steps of finishing a journal article, specifically writing an
abstract and composing a title:
266
■
Moves of an abstract
■
Use of tense in an abstract
■
Use of passive and active voice in an abstract
■
X of Y by Z pattern commonly used in titles
■
Use of capitalization in titles
■
Relationship between a title, an abstract, and a computer search
The Journal Article
Additional Exercises
Exercise 7.10
The following abstract (adapted from an original source, identified in the
Instructor’s Answer Key) has 277 words, but it must have no more than 250
words to be submitted for publication.
a. Edit the abstract so that it has no more than 250 words.
b. Propose a title for this paper based on the content of the abstract. Use the
standard X of Y by Z pattern, if possible. Follow capitalization rules when
finalizing your title.
Abstract. The explosion and collapse of the World Trade Center (WTC) was a
catastrophic event that produced an aerosol impacting many workers, residents, and
commuters during the first few days after September 11, 2001. During the initial
days that followed the collapse, 14 bulk samples of settled dust were collected at
locations surrounding the epicenter of the disaster, including a single location that
was located inside of a building. Some of the samples collected from these various
sites were analyzed for a variety of different potential hazards, such as inorganic and
organic constituents, as well as morphology. The results of analyses for a wide variety
of persistent organic pollutants are described herein, including polycyclic aromatic
hydrocarbons, polychlorinated biphenyls, and select organochlorine pesticides on
settled dust samples. The 86 -PCBs comprised less than 0.001% by mass of the bulk
in the three bulk samples analyzed indicating that PCBs were of limited significance
in the total settled dust across lower Manhattan. Likewise, organochlorine pesticides,
including chlordanes, hexachlorobenzene, heptachlor, 4,4-DDE, 2,4-DDT, 4,4-DDT,
and Mirex, were found at low concentrations in the bulk samples. Conversely, the
37-PAHs comprised up to nearly 0.04% ( 0.005–0.039%) of the bulk in the six bulk
samples analyzed. Further size segregation of three initial bulk samples and seven
additional samples indicated that 37-PAHs were found in higher concentrations on
relatively large particles (10–53 μm), representing up to 0.04% of the total dust mass.
High concentrations were also found on fi ne particles ( 2.5 μm), often accounting for
~0.005% by mass. Taking all of these many factors into consideration, we estimate that
approximately 100–1000 tons of 37-PAHs were spread over a localized area immediately
after the WTC disaster on September 11. (277 words)
Exercise 7.11
Read and revise the following abstracts so that they are more in line with the
abstracts presented in this chapter:
Abstract. Laponite and tempamine were used to compose thin films that were studied
by electron paramagnetic resonance and AFM. These studies prove that Laponite fi lms
Writing the Abstract and Title
267
are oriented and that orientation disappears with age. Laponite films create ordered
barriers that confi ne movement of incorporated molecules. Further studies, summarized in the Introduction, involve the investigation of films assembled with additional
compounds, such as polymers, that are envisaged to produce ordered films with useful
mechanical properties.
Abstract. Grignard reactions are of utmost importance in organic synthesis (Lee,
2005), and fi nding the prime conditions under which to conduct these reactions is
really crucial to their usefulness. This work looks at the effects of time, and temperature on yield in the reaction of isopropyl magnesium bromide with 4-methoxybenzaldehyde to produce 1-(4-methoxyphenyl)-2-methylpropan-1-ol. The reaction was
fi rst run for 10 min at 25, 50, 75, and 80 °C. Next it was run at 80 °C for 10, 20, and
30 min (see Methods section for more details). Highest yields (85%) were obtained at
80 °C with 10–20 min reaction times. Utilizing conditions that optimize yields will
improve the economic practicality of these reactions, and increase their usefulness
as a synthetic tool.
Exercise 7.12
Reflect on what you have learned about writing an abstract, a title, and the journal article as a whole, now that you are just about done writing your own journal
article. Select one of the reflection tasks below and write a thoughtful and thorough response.
a. Reflect on the importance of the abstract and title of a journal article.
■
■
■
■
In what ways do the abstract and title prepare readers for the contents of
the paper?
What are the keys to an effective abstract and title?
What makes writing an abstract and title challenging?
How might you minimize the challenge(s) to make the task easier?
b. Reflect on your experience writing a journal article, from start to finish.
■
■
■
■
268
How have your views of scientific writing changed while writing your
journal article?
What have you learned that has assisted you most in writing your journal
article?
What have you learned that will make you a better reader of the professional literature?
How successful have you been with your journal article? What will you do
in the future to write an even more effective journal article?
The Journal Article
Peer Review Practice: Title and Abstract
Imagine that a friend has asked you to review the title and abstract of a paper
that is being written with other researchers on chromated copper arsenate (CCA),
a compound used to preserve wood. The research team examined the chemical
structure of arsenic (As) and chromium (Cr) in CCA to determine if the oxidation
state of As and Cr changed over time due to weathering.
Using parts 2 and 3 of the Peer Review Memo on the Write Like a Chemist Web
site, review the title and abstract below. Provide specific suggestions in your memo
to help your friend improve the title and abstract. (The title and abstract below are
adapted from an original source, noted in the Instructor’s Answer Key.)
The Implications of Environmental Weathering: The Chemical Structure of Arsenic
and Chromium in Wood Treated with CCA
1 X-ray Absorption Spectroscopy (XAS) is used to evaluate the chemical structure of As
2 and Cr in three samples of CCA-treated materials: newly treated wood, aged wood (5
3 years as decking), and dislodgeable residue from aged (1–4 years as decking) CCA4 treated wood. Chromated copper arsenate (CCA) has been used to treat lumber for over
5 60 years to increase the expected lifetime of wood. Since arsenic and chromium are
6 involved in CCA-treated wood, attention has become focused on the potential risks of
7 this practice. In particular, exposure of children to arsenic from CCA-treated wood used
8 in decks and play sets has received considerable attention. We found several important
9 findings in this study. First, Cr and As have the same forms in fresh and aged CCA10 treated materials and in dislodged residue. In all cases, the dominant oxidation states
11 are: As(V) and Cr(III). Second, the local chemical environment of the two elements
12 is best represented as a Cr/As cluster consisting of a Cr dimer bridged by an As(V)
13 oxyanion. Long-term stability of the As/Cr cluster is suggested by its persistence from
14 the new wood through the aged wood and the dislodgeable residue.
Writing the Abstract and Title
269
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Module 2
The Scientific Poster
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8
Writing the Conference Abstract and Title
All too familiar words from research mentor to student: “I’d like
you to submit an abstract to the upcoming ACS conference on your
research. The submission deadline is in two weeks. Unfortunately,
I’ll be out of town, but I’m sure you can write it on your own.”
This chapter focuses on writing a conference abstract, not to be confused with a
journal article abstract, which was addressed in chapter 7. A conference abstract
is submitted in response to a Call for Abstracts issued by conference organizers,
typically 3–6 months before the conference takes place. The abstract is reviewed
and, if accepted, allows the authors to present a contributed paper (as either an
oral or poster presentation) at a conference session. Only accepted papers may be
presented at a conference; whether they are oral or poster presentations is a decision usually made by conference organizers. By the end of this chapter, you will
be able to do the following:
■
Describe the major purposes of the conference abstract
■
Recognize a typical organizational structure for the conference abstract
■
Identify common writing conventions in the conference abstract
■
Write a concise and informative conference abstract with title and author list
The Writing on Your Own tasks throughout the chapter will guide you as you do
the following:
8A Prepare to write
8B Decide on an organizational structure
8C Draft your conference abstract and title
8D Fine-tune your conference abstract and title
Conference Abstract
A short text, written in response to a Call for Abstracts, that describes the work to be
presented at a conference. Minimally, the abstract includes a title, author list and affiliations,
and a short description of the work to be presented.
Contributed Paper
An oral or poster presentation given at a conference. A paper can only be presented
after an abstract is submitted by the authors and then accepted by conference
organizers.
Conference Session
Because most chemistry conferences address multiple areas of chemistry, abstracts are
usually submitted to a division of chemistry (e.g., Division of Organic Chemistry) and to a
specific session within that division (e.g., Asymmetric Reactions and Syntheses Session of
the Division of Organic Chemistry).
Writing a conference abstract is often the first professional genre that novice
writers tackle on their own, with little, if any, guidance from their research mentors. This chapter is intended to prepare you for the task by focusing on the text
of the abstract. (If your abstract is accepted and results in a poster presentation,
see chapters 9 and 10 for guidance in preparing the poster.)
Like the journal article abstract, most conference abstracts have strict word
limitations (typically between 150 and 200 words). Adherence to this limit is
expected; your abstract will likely be rejected if the limit is exceeded. Many other
formatting specifications must also be followed. For example, most instructions
include rules for formatting your title, author list, graphics, and special characters (e.g., µm, , , m3). The reason for such specificity is that your abstract,
if accepted, will be printed (as is) in conference proceedings. Adherence to
these guidelines by all authors ensures that the proceedings appear uniform and
professional.
Conference Proceedings
A written record of conference sessions and events, including a schedule and abstracts of
all conference presentations.
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Because they both include the word “abstract”, you may think that a conference abstract is just like a journal article abstract. In fact, a conference abstract
combines features of both the Introduction section and abstract of a journal article. Like the Introduction, a conference abstract introduces work that will be presented (in this case, at a conference). Like the journal article abstract, a conference
abstract highlights significant findings.
Reading and Analyzing Writing
We begin by asking you to read and analyze two excerpts. Excerpt 8A includes a
partial list of instructions available to authors planning to submit an abstract to
the 233rd American Chemical Society (ACS) national meeting, held March 2007.
Excerpt 8B is an abstract for a paper that was presented at that meeting.
Exercise 8.1
As you read excerpts 8A and 8B, complete the following tasks:
a. Revise the following title so that it adheres to conference guidelines:
The Factors That Affect Indoor Air Quality: Exposures to Carbonaceous
Aerosols
b. The abstract contains seven sentences (149 words). Briefly state the purpose
of each sentence. Based on these purposes, propose a move structure for the
conference abstract.
c. Identify the intended audience(s) for the abstract. Give reasons for your
answer.
d. Articulate two rules, one on the use of abbreviations and the other on the use
of personal pronouns (e.g., I, our, we) in the abstract.
e. Identify the verb tenses used in excerpt 8B. State the function(s) of each
tense.
f. Specify two or three keywords from the title and text of excerpt 8B that
would facilitate an electronic search, permitting easy retrieval and/or indexing of the abstract.
Excerpt 8A (adapted from Instructions for Authors. On Line Abstract Submission System for ACS
Conferences (OASYS). http://oasys.acs.org/acs/233nm/oasys.htm (accessed January 2008))
Abstracts should be 150 words or less. Abstracts may contain one or more graphics.
The number of words you can submit may depend on the size of your graphic file (the
Writing the Conference Abstract and Title
275
program will automatically enforce a size restriction), but if you exceed the maximum
word count because your graphic is too large, you can scale your graphic in OASYS.
Styles to Observe
The abstract should be entered using the following style:
■
The title is in sentence case, with only the first letter of the title capitalized, except
words that are proper nouns, acronyms, or words that follow a colon. Here’s an
example:
My theories on recombinant DNA: Or, how I spent my summer vacation
■
The title is not in bold or italics, except as needed (e.g., foreign words).
■
The title does not begin with The or A (these will be removed by our editors).
■
The abstract text does not contain the word “abstract” or any author names.
■
The abstract text does not contain footnotes.
■
The author names do not contain titles or suffi xes (suffi xes such as “III” can be used).
Excerpt 8B (from Russell and Bahadur, 2007)
Predicting nanoparticle interfaces with molecular dynamics
Lynn Russell and Ranjit Bahadur. Scripps Institution of Oceanography, University of
California, San Diego, CA
Nanoparticles exhibit physical properties that reflect the boundary between gaseous and
condensed phases, sometimes resulting in behavior that is not predicted by bulk-phase
approaches. Recent advances in nanoparticle measurements mean that our theoretical
understanding sometimes lags our experimental observations of nanoparticle behavior.
To address this gap, molecular dynamics (MD) simulations were designed to investigate
the behavior of phase transitions in nanoparticles, in particular their water uptake. Our
work addresses the dissolution of nanoparticle salt crystals in condensed water and the
surface tension of nanoparticle interfaces that affect the water uptake process. MD simulations have shown that voids play a necessary role in initiating short time scale
(1 ns) dissolution. We have also used MD simulations to predict the size dependence of
liquid-vapor, solid-vapor, and solid-liquid interfaces for the NaCl-water-air systems. The
results indicate Tolman lengths near 0.1 nm for liquid interfaces and below zero for a
solid-vapor interface. (149 words)
Analyzing Audience and Purpose
A conference abstract is written for two distinct audiences. Conference organizers
represent the first audience; they read the abstract and decide whether to accept
it for a conference paper. Several factors influence this decision, not the least of
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which is the quality of writing in the abstract. A poorly written abstract often
leads to a poorly prepared conference presentation; hence, such abstracts are easy
for reviewers to dismiss. Other factors include the appropriateness of the abstract
topic (does it fit the theme of the conference session?), the quality of the science,
and how far the research has progressed. Conferences are forums for presenting
new, even late-breaking, results. However, an abstract may be rejected if the work
is too new or appears to lack sufficient data to ensure a quality presentation by
the time of the conference. (If you find yourself using phrases such as “we will
measure” or “we propose to analyze” repeatedly in your abstract, you may want to
consider postponing your submission.)
Alternatively, an abstract should not be submitted if the content is too old. For
example, an abstract describing work that is already published should not be submitted. Similarly, abstracts describing results that have already been presented at
other national conferences should not be submitted, unless significant new progress has been made. Some overlap with previous presentations is allowed (after
all, new science builds on past accomplishments), but a good rule of thumb is that
at least 75% of the content should be new. (Note: This rule is often relaxed if the
conference is local or university-based.)
The second audience comprises conference attendees, who read abstracts to
determine whose talk to attend or poster to view. Because national conferences
typically have multiple concurrent sessions, attendees rely on abstracts to make
their decisions about what sessions to attend, where to go, and when. Individuals
who read your abstract are likely to be in a related field of chemistry, but most
likely will not be in your specific area of chemistry. Thus, it is important to
keep your abstract general enough to be readily understood across different
areas of science, thereby targeting primarily a scientific audience. In this regard,
the conference abstract is more similar to the Introduction section of a journal
article than to the abstract of a journal article, the latter written for an expert
audience.
8A Writing on Your Own: Prepare to Write
Locate, and then read, the Call for Abstracts and Instructions for Authors for a conference that you plan to attend. Alternatively, use excerpt 8A for this assignment. How long
should the abstract be? What special formatting is required? When is the deadline for
submission?
Consider what aspects of your research you want to present. Classify your work into
three groups: (1) completed work, (2) nearly completed work, and (3) work that you hope
to complete. Base your abstract largely on work in the first two categories. If this is not your
first abstract submission, be sure that you have not presented too much of this work at
another national conference.
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277
Analyzing Organization
A typical move structure for the conference abstract is shown in figure 8.1. The
first move identifies the research topic and suggests why the research is important. These two submoves parallel the first two submoves of the journal article
Introduction section (see figure 6.1). The key difference is the absence of a third
submove in the conference abstract; unlike the journal article Introduction, the
conference abstract devotes little, if any, space to background information or
a review of others’ works. Recall that the primary purposes of the conference
abstract are to tell readers about the work that you will present and to help them
decide if they should attend your session. Thus, summarizing others’ works is of
little use in this regard. Because background information is deemphasized, there
are typically no citations in a conference abstract. If citations are included, full
references must also be provided so that the abstract can stand on its own.
Moves 2 and 3 of the conference abstract also parallel the moves of the journal
article Introduction. Move 2 points out a gap in the field (e.g., a problem that
needs to be solved, work that needs to be done) and serves as a transition to
move 3, which describes the work to be presented. Depending on the goals of
the project, different aspects of the work may be highlighted. In some instances,
methods will be emphasized; in others, results will be the focus of attention.
When possible and appropriate, numerical data should be included in the conference abstract. If this is not possible, because you are still completing parts of the
work, at least state in the abstract what data will be presented at the conference
(e.g., “Arsenic levels from two different lakes will be reported.”). Results are the
1. Introduce the Research Area
1.1 Identify the topic
1.2 Highlight the importance of the research
2. Suggest a Gap in the Field
3. Describe the Work to be Presented
(i.e., the methods used and the results obtained or to be obtained)
Figure 8.1 A visual representation of the move structure for a typical
conference abstract.
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punch line of the research story, and an abstract without a punch line is not very
satisfying.
Authors who follow the moves depicted in figure 8.1 when writing their conference abstracts will meet most chemists’ expectations, but variations are also
quite common. For example, authors place varying degrees of emphasis on the
different moves. Some authors focus on moves 1 and 2, while others concentrate
on move 3. Some even skip moves 1 and 2 entirely. We examine a few such variations in the excerpts that follow.
Analyzing Conference Abstracts
We are now ready to read and analyze abstracts in more depth. We begin by looking at a set of abstracts to identify similarities and differences in organization,
emphases, and content. We then summarize writing conventions that run across
most conference abstracts.
Analyzing Excerpts
In this section, we analyze abstracts that were published in the proceedings of the
233rd ACS national meeting. Abstracts from three different divisions are examined: Division of Agricultural & Food Chemistry, Division of Environmental
Chemistry, and Division of Organic Chemistry.
We begin by analyzing abstracts (printed in their entirety) that follow the
move structure in figure 8.1. To facilitate analysis, we identify moves 1, 2, and
3 and include a word count at the end of each abstract. In this way, you can see
for yourself how much emphasis the authors placed on each move. (Note that
in some cases, 200-word abstracts were permissible, so do not be surprised if
abstracts exceed 150 words.)
In excerpts 8C and 8D, moves 1 and 2 are accomplished in a single sentence.
(In one case, two statements are linked by a semicolon; in the other case, two
statements are linked by “but.”) In just a few words, the topic is identified and a
gap is suggested. The remainder of both abstracts is devoted to move 3. Methods
are mentioned briefly, but results are emphasized and numerical values are
included. Both abstracts conclude with a sentence that states the implications of
the work—specifically, that litter mercury is accumulating in soils (excerpt 8C)
and that stored beer maintains phytonutrients (excerpt 8D). Abstracts do not
typically end in this way, in part, because when abstracts are written, implications are usually not known. However, if implications are known, they are often
included. (Implications of the work are nearly always addressed in the final oral
or poster presentation.)
Writing the Conference Abstract and Title
279
Exercise 8.2
Read excerpts 8C and 8D and answer the following questions:
a. Do the authors transition from moves 1 and 2 to move 3 in the same way or
in a different way? Explain.
b. Identify the numerical values (and units) that are reported in each abstract.
What formatting conventions are followed?
c. What verb tense is used in the last sentence of each abstract? Justify this
choice.
Excerpt 8C (from Bushey et al., 2007)
[Move 1] Plant leaf tissue has been documented to contain significant amounts of mercury (Hg); [Move 2] however, the role of leaf tissue Hg relative to atmospheric deposition
and soil pools of Hg is not well established. [Move 3] A quantitative investigation was
conducted to assess the role of plants in the deposition and fate of mercury within an
upland forest watershed and the potential implications for soft-water lake ecosystems
of the northeastern USA. Plant tissue samples were collected over a two-year period.
Leaf mercury content increased approximately 10-fold over the growing season with
average uptake rates of 0.21–0.35 ng/g-day. Uptake varied by species and was consistent between the two growing seasons. Leaf total Hg content reached 47–62 ppb within
fresh litterfall samples. An annual flux of 180 mg of total Hg per hectare was estimated,
representing the largest ecosystem input of Hg. Hydrologic modeling of upland runoff
and litter decomposition results suggest that this litter mercury is accumulating within
upland soils. (158 words)
Excerpt 8D (from Rohrer and Majoni, 2007)
[Move 1] The health benefits of beer phytonutrients, such as reduction in coronary heart
disease, have been reported, [Move 2] but little information is available on changes in
phytonutrients under household refrigerated storage. [Move 3] The objective of this study
was to determine the phytonutrient concentration in non-alcoholic beer beverages and
one alcoholic beer during 60-day storage. Phytonutrient concentration was evaluated as
the total polyphenol content and the flavonoid content [( )-catechin and (–)-epicatechin].
Results found a significant increase (p 0.05) in total polyphenol content in all beer beverages except one non-alcoholic beer. Overall, total polyphenol (505 mg/L) and ( )-catechin content (0.52 mg/L) in O’Doul’s non-alcoholic beer were greater than in the other
non-alcoholic beverages. This increase during storage indicates that consuming stored
beer beverages after two months still allows health benefits to be attained. (129 words)
Next, consider excerpt 8E. Like the abstracts in excerpts 8C and 8D, this abstract
accomplishes moves 1 and 2 quickly, in just two sentences. However, because this
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abstract is about a new method, the authors use most of the abstract to describe
that method (Köhler theory analysis), and no results are reported. The authors
do indicate, however, that results from a diverse set of aerosol sources will be
presented at the conference.
Exercise 8.3
Read excerpt 8E and answer the following questions:
a. What phrase do the authors use to signal the end of the description of their
new method?
b. What phrase do the authors use to transition from the description of their
method to the results that they intend to present at the conference?
c. The authors use present tense to describe their methods (e.g., “surfactant
properties are characterized”) rather than past tense (“surfactant properties
were characterized”). Find two more examples of present tense in the methods description. Propose a reason for this verb tense choice.
Excerpt 8E (from Nenes et al., 2007)
[Move 1] Quantifying the impact of water soluble organic compounds (WSOC) on cloud
droplet formation constitutes a substantial source of uncertainty in aerosol-cloud climate
interaction studies. [Move 2] This uncertainty is a consequence of the plethora and
complexity of the compounds that constitute atmospheric organic matter; methods for
characterizing its interaction with water vapor are few and require further development.
[Move 3] This study focuses on a new method, termed “Köhler theory analysis”, to characterize the average solubility, molar mass, surfactant characteristics, and droplet growth
kinetics of minute amounts of WSOC samples typically collected from an aerosol sampler. Surfactant properties are characterized by surface tension and contact-angle measurements with a pendant drop method tensiometer. Water soluble mass is characterized
by a functional group analysis, by separating the samples into hydrophilic, hydrophobic, and deionized components. Finally, the droplet growth kinetics and cloud droplet
formation potential of all carbonaceous samples are measured using a Continuous Flow
Streamwise Thermal Gradient Cloud Condensation Nucleus counter. We will present
results from a diverse set of sources such as rural biomass burning, urban Atlanta aerosol, Mexico City aerosol, and in situ stratocumulus cloudwater samples collected aboard
the CIRPAS Twin Otter. (188 words)
Exercise 8.4
Read excerpt 8F. While doing so, complete the following tasks:
a. Identify moves 1 and 2. (Note: move 2 is not a typical gap statement but does
imply work that needs to be done.)
Writing the Conference Abstract and Title
281
b. Consider move 3. Is it more in line with excerpts 8C and 8D (which focus
principally on results), excerpt 8E (which focuses mainly on methods), or
neither? Justify your answer.
c. Comment on the authors’ use of personal pronouns (e.g., I, we, our), verb
tense (past, present, and/or future), and voice (active and/or passive).
d. Repeat (c) above for the abstracts in excerpts 8B–8E. What similarities
and differences do you notice across all abstracts examined thus far in the
chapter?
Excerpt 8F (from Zuo et al., 2007)
Flavonoids are an important natural pigment and are widely distributed in vegetables,
berries, and fruits. Interest in the separation and determination of fl avonoid and other
phenolic compounds in plants has increased in past decades because these compounds
have definitive anticarcinogenic and cardioprotective effects on humans. In this work,
two flavonol glycosides, quercetin galactoside and quercetin arabinoside, were identified
in American cranberry fruit. Analyses included separation, hydrolysis, and structure
elucidation of flavonol glycosides. The separation was carried out by solvent extraction,
thin-layer chromatography, and high performance liquid chromatography (HPLC).
After hydrolysis of the obtained flavonol glycosides, fl avonol aglycones and sugars were
identified by HPLC and gas chromatography-mass spectrometry (GC-MS), respectively.
(109 words)
We now consider the abstract presented in excerpt 8G, which reverses the
emphases observed in excerpts 8C–8F. In excerpt 8G, moves 1 and 2 comprise
the bulk of the abstract, and move 3 is just a single sentence. Much of the abstract
is used to elucidate important gaps in the field: that (1) a size-based standard for
regulating atmospheric particulate matter is inadequate because it does not take
into account chemical composition, and (2) compositional analyses are difficult,
especially for metals, because they often exist in multiple oxidation states. These
gaps help to establish the relevance of the authors’ work. Only in the last sentence
do the authors mention their work specifically (move 3). Here, they identify their
method (micro-XANES) and tell readers what results will be presented at the
conference.
Excerpt 8G (from Nico et al., 2007)
[Move 1] Currently atmospheric particulate matter is regulated based on various size
categories because of the apparent association between particle size and adverse health
effects. [Move 2] However, the current size-based understanding of atmospheric particles
is relatively crude because it does not account for differences in the chemical composition of these particles. Presumably a chemically reactive particle has a greater potential
for damage than a chemically inert particle of comparable size. Of the metals potentially
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released as aerosols, Cr is of particular interest because of its potential to exist in at
least three oxidation states of very different toxicities: metallic Cr, which is used in a
variety of industrial processes, Cr(III), which is an essential, non-toxic micronutrient,
and Cr(VI), which is a strong oxidizer, highly toxic and carcinogenic. [Move 3] We have
employed micro-X-ray absorption near edge spectroscopy (micro-XANES) to determine
the chemical form of chromium in ambient PM 2.5 collected from several locations in
northern California. (150 words)
We next consider excerpts 8H and 8I, two abstracts that describe chemical syntheses. In each case, roughly equal space is given to moves 1 and 2 and to move
3. Both abstracts indicate that successful syntheses have been accomplished,
although details about the syntheses (e.g., stoichiometry, reaction conditions, and
product yields) are not included in the abstract (but will be available at the conference). Note the inclusion of a graphic in excerpt 8I. Graphics are allowed in most
abstracts, although their inclusion often limits the number of words that can be
used. If you plan to include a graphic in your abstract, be sure to check instructions for how to prepare the graphic (i.e., software programs to use) and save the
file (e.g., as HTML, GIF, or JPEG).
Excerpt 8H (from Jiao and Smith, 2007)
[Move 1] 2,2-Bipyrroles are key synthetic precursors for porphycenes, corroles, saphyrins, and other expanded porphyrin analogs. Most of the current bipyrrole syntheses are
mainly based on an Ullmann dimerization reaction of a preformed pyrrole or on oxidative coupling. [Move 2] However, the Ullmann reaction for bipyrrole synthesis generally
requires high temperatures and thus few functional groups can survive the conditions.
Moreover, the type of bipyrroles accessible from the Ullmann reaction and from oxidative coupling is very limited and many bipyrroles are still inaccessible or can only be
obtained in low yields. Although some improvements have recently been made to bipyrrole synthesis, tedious synthetic routes are still involved and yields are low. [Move 3] We
have developed an efficient novel synthetic route to synthesize bipyrroles and eventually porphycenes based on a Pd(0)-catalyzed reaction. In this novel synthetic route, the
reaction can be performed at room temperature under very mild reaction conditions and
provide good yields of bipyrroles in most cases. The synthesis of a series of bipyrroles
using this novel synthetic route will be presented and the scope and limitations of the
reaction will be discussed. Further usage of the bipyrroles in synthesis of porphycenes
will also be reported. (192 words)
Recently
The ACS Style Guide recommends avoiding the word recently in articles and books. This
recommendation is relaxed in conference abstracts. However, recently is a good word to
cut if you are near the abstract word limit.
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283
Excerpt 8I (from Arimitsu et al., 2007)
[Move 1] Furans and hydrofurans are well known compounds found in natural products
and pharmaceuticals; currently, the synthesis of these compounds using catalytic methods
constitutes an important focus of research. [Move 2] Although fluorine substituted furans and
hydrofurans are attractive targets from a biological standpoint, there are few reports on practical methods for preparing them, and no method is catalytic. [Move 3] Recently, a cost-effective
synthesis of gem-difluoro homopropargyl alcohols 1 was reported by our group. Using the
triple bond of gem-difluoro homopropargyl alcohols 1 as a synthetic handle, we have uncovered novel transformations toward fluorinated furans and hydrofurans. (94 words)
R
R
F
F
O
1) ICI
2) Pd(0), R-I
R
R
F
R
1
F
1) AgNO3
2) Silica-gel
R
HO
O
R
1) AgNO3
2) Pd/H2
F
O
F
R
The abstracts in excerpts 8B–8I all follow the moves in figure 8.1, although not
in exactly the same manner. The difference is in how much emphasis the authors
place on each move. We conclude this section by examining two abstracts that do
not follow the move structure. In excerpts 8J and 8K, moves 1 and 2 are skipped
entirely, and only move 3 is addressed. The advantage of this approach, which is
quite common, is that authors can focus solely on the work that will be presented,
without allocating precious space to less essential information.
Excerpt 8J describes a chemical synthesis. It is quite short (55 words) and
includes a graphic. “This work” (i.e., the work to be presented) is addressed in the
first sentence. Compound labels (bolded numbers 1, 2, 3, and 4) are used to link
the compounds named in the text to their respective structures in the graphic.
Excerpt 8K is longer (150 words). Again, the authors mention their own work in
the first sentence (the fractionation and analysis of cranberry fruit for flavonoids).
However, flavonoids are not defined, their importance is not emphasized, and no
gap is suggested.
Bolded Numbers
See “Abbreviations, Acronyms, and Compound Labels” in appendix A for more on bolded
numbers.
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Excerpt 8J (from Lee et al., 2007)
[Move 3] This work surveys complementary routes for the synthesis of pyrazolo[1,5-]
pyrimidine-7-ones 1 and pyrazolo[1,5-]pyrimidin-5-ones 2. The use of 1,3-dimethyluracil 3 as an electrophile for pyrimidine ring construction affords pyrazolo[1,5-]
pyrimidin-5-ones 2, contrary to literature reports. Novel use of trans-3-ethoxyacrylate
4 as an electrophile also afforded 2, and the isolated intermediates from this reaction
support our proposed mechanism. (55 words)
O
O
R1
N N
R1
N
H
R2
1
N N
N
H
R2
CO2Et
N
2
O
O
N
3
EtO
4
Excerpt 8K (from Liberty et al., 2007)
[Move 3] Cranberry fruit of Early Black cultivar was fractionated chromatographically
and fractions were analyzed for fl avonoid content. The effects of the flavonoid fractions
and ursolic acid, an abundant triterpenoid in cranberry peel, were assessed in two
models of colon cancer and one model of breast cancer. Clonogenic soft agar assays were
used to determine the effect of these compounds on tumor colony formation in HCT-116,
HT-29 and MCF-7 cells. MTT and trypan blue assays were performed to assess their
ability to inhibit tumor cell proliferation. TUNEL assays were performed to assess apoptotic response to the cranberry compounds. The proanthocyanidins inhibited tumor
colony formation in HCT-116 and HT-29 cells in a dose-dependent manner, with greater
effect on the HCT-116 cell line. Ursolic acid strongly inhibited tumor colony formation
in both colon cell lines. These compounds also decreased proliferation in all three tumor
cell lines with the HCT-116 cell line most strongly affected. (150 words)
Exercise 8.5
Compare the two abstracts about flavonoids in excerpts 8F and 8K. Excerpt 8F
includes moves 1–3; excerpt 8K includes only move 3. Which approach do you
prefer? Explain your choice.
Exercise 8.6
Sentences a–f below are all from conference abstracts. Read each sentence and
indicate which move the sentence accomplishes (move 1, 2, or 3). Refer to figure 8.1
as needed.
a. Single-walled carbon nanotubes (SWNTs) are filamentous manifestations of
a repeating aromatic carbon structure formed into an open cylinder. (From
Ferguson and DeMarco, 2007)
Writing the Conference Abstract and Title
285
b. We have developed a novel method of estimating the fraction of open-ended
carbon nanotubes in samples with porosity accessible for adsorption and gas
storage. (From Agnihotri et al., 2007)
c. The discovery that negatively charged aggregates of C60 are stable in aqueous
environments has elicited concerns regarding the potential environmental
and health effects of these aggregates. (From Duncan and Vikesland, 2007)
d. However, the specific electronic properties of individual nanotubes remain
untapped on the industrial scale. (From Jackson and Scott, 2007)
e. The synthesis, properties, and dynamic reactions of four heteroaromatic
systems will be presented. (From Philp, 2007)
f. The purpose of this investigation was to better understand the behavior of
multiwalled carbon nanotubes (CNTs) during a simulated drinking water
treatment process. (Adapted from Mansfeldt et al., 2007)
8B Writing on Your Own: Decide on an Organizational Structure
Review the move structure in figure 8.1 and the various ways in which authors have
adapted these moves in excerpts 8B–8K. In addition, consider the data that you want to
present and whether you will include a graphic in your abstract.
With these considerations in mind, sketch out a move structure for your abstract.
Estimate how much space you will devote to each move and which move(s) will
be assigned the most and least importance. For guidance, consider browsing
through the Technical Program Archive of past national meetings on the ACS
Web site.
Writing an Abstract Title
A title must be submitted with the conference abstract. Because only the title,
author list, and abstract are printed in the conference proceedings, the title is one
of the few ways that interested individuals will be able to find your presentation.
Hence, the title should be highly informative and use keywords that others in your
field will recognize. If you plan to present a poster, keep in mind that your title
should be short enough to fit on a single line across the top of your poster. A few
examples of abstract titles included in the Proceedings of the 231st American Chemical
Society National Meeting in Atlanta, Georgia (March 26–30, 2006) are listed below.
Note that titles follow the same structure as journal article titles (see table 7.1).
1. Analysis of Bluntnose Minnow Growth in Differently Treated Mine Water
2. Direct Electron Transfer at the Anode of an Ethanol/Air Biofuel Cell
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3. Enantioselective Biodegradation of Metalaxyl by Sewage Sludge and
Screening Bacteria
4. On the Cooling Time of an Orange in the Refrigerator
5. Use of Pumpkin Pectin for Concentration of Ions of Heavy Metals
Abstract Titles
Abstract titles often follow an X of Y by Z pattern (see table 7.1).
Exercise 8.7
Examine abstract titles 1–5 above and answer the following:
a. Which titles follow the X of Y by Z pattern presented in table 7.1? Explain.
b. Make a list of keywords that others in the field might recognize.
Adding an Author List
A complete list of authors (not just the presenting author) and their affiliations
should be submitted with the conference abstract (e.g., see the author list in
excerpt 8B). Review abstract guidelines for formatting instructions. Typically,
first and last names of all authors (e.g., Wilhelmus H. J. Boesten) are included.
The sequencing of authors varies with each area of chemistry. The author giving the presentation is often listed first or distinguished with an asterisk or
underlining.
Analyzing Writing across the Conference Abstract
Many of the writing conventions used in conference abstracts are those used in
other chemistry genres. Important conventions are summarized here.
■
Abbreviations and acronyms: As with the journal article abstract, most
abbreviations and acronyms are defined at first use in the conference abstract
(e.g., MD for molecular dynamics in excerpt 8A, WSOC for water soluble
organic compounds in excerpt 8E, micro-XANES for micro-X-ray absorption
near edge spectroscopy in excerpt 8G). Abbreviations and acronyms need
not be defined in the conference abstract if they are not considered essential
for understanding the work (e.g., CIRPAS Twin Otter, the name of a ship, in
excerpt 8E).
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287
■
Citations: It is rare to see citations in conference abstracts. If a citation
cannot be avoided, a full reference must be included in the abstract
(see chapter 17).
■
Keywords: A list of keywords is not included in a conference abstract (as it
is in a journal article abstract), but it is wise to use keywords in the abstract
text and title. The inclusion of keywords facilitates electronic searches, making the work more accessible to others interested in your field.
■
Verb tense: Verb tenses in conference abstracts are consistent with conventions described elsewhere in the textbook (e.g., see tables 4.1, 5.1, 6.5). For
example, past tense is used to describe work done in the past (e.g., “The
rates were measured”), and present tense is used to make statements of fact
or state information that is expected to be true over time (e.g., “Furans are
found in natural products”). Some authors use future tense (in active or passive voice) in conference abstracts to refer to the work that will be presented
(e.g., “We will present these findings” and “The synthesis will be presented”).
Others prefer to state such intentions in present tense–passive voice
(e.g., “The findings are presented”).
■
Voice: Both active and passive voice are used in conference abstracts. Active
voice is especially common in move 1 (e.g., “2,2-Bipyrroles are key synthetic
precursors”) but is also used in the rest of the abstract. Passive voice is often
used to refer to work done in the past (e.g., “Molecular dynamics simulations
were designed to investigate . . . nanoparticles”).
■
We: The word we often appears in conference abstracts, particularly in move 3
(e.g., “We have used” and “We will present”). In cases where there is a single
author, I is used.
Exercise 8.8
Sentences a–f are all from conference abstracts. Select the correct verb for each
sentence based on the move or submove indicated.
a. Sonication and heat treatment are/were common steps employed during
purification of as-produced nanotubes. [Submove 1.1] (From Agnihotri
et al., 2007)
b. Thermal-optical analysis (TOA) is/was widely used to classify carbonaceous aerosol into organic and elemental carbon. [Submove 1.1] (From
Subramanian et al., 2007)
c. However, the Ullman reaction . . . generally requires/required high temperature
and thus few functional groups can survive. [Move 2] (From Jiao and Smith,
2007)
d. The rates of superoxide and singlet oxygen production are/were measured
for three distinct varieties of fullerene suspension. [Move 3] (From Hotze
et al., 2007)
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e. The performance of the simulated process is/was monitored by nephelometric
turbidity, pH, and UV–vis absorbance. [Move 3] (Adapted from Mansfeldt
et al., 2007)
f. Further usage of bipyrroles in the synthesis of porphycenes was also
reported/are also reported/will also be reported. [Move 3] (From Jiao and
Smith, 2007)
8C Writing on Your Own: Draft Your Conference Abstract and Title
Using the organizational structure developed in Writing on Your Own task 8B, write
the first full draft of your conference abstract, title, and author list. Remember to
define abbreviations and acronyms that are critical to understanding your work,
incorporate keywords into your abstract and title, and use tense and voice in conventional ways. Avoid the use of citations. Make sure that you write for the appropriate
audience.
8D Writing on Your Own: Fine-Tune Your Conference Abstract and Title
Find several people (including all co-authors) to read over the draft of your abstract and
give you feedback. You will benefit the most by finding readers who can evaluate your
abstract both for its scientific merit and writing quality. Another pair of eyes will catch
mistakes that you have missed.
Do not submit your abstract until it has been peer reviewed and you have had the
chance to improve it. Some online abstract submission programs allow you to edit your
work up until the abstract deadline. After that date, no revisions are allowed. Before the
deadline arrives, double-check your word count, capitalization, spelling, punctuation,
units, and other writing conventions. See chapter 18 for additional hints on finalizing
your work.
Chapter Review
Check your understanding of what you’ve learned in this chapter by defi ning
each of the following terms for a friend or colleague who is new to the field:
abstract title
conference proceedings
author list
conference session
conference abstract
contributed paper
Writing the Conference Abstract and Title
289
Also, answer the following questions for a friend who has just been encouraged
to submit a conference abstract:
■
What is the purpose of the conference abstract?
■
What audience should be addressed in the conference abstract?
■
How are conference abstracts and journal article Introduction sections similar? How are they different? What are the similarities and differences between
conference and journal article abstracts?
■
What are the typical moves of a conference abstract? What are some common
variations of these moves?
■
What are common writing conventions regarding the use of verb tense, voice,
and personal pronouns in a conference abstract?
■
What information should be included in the title and author list?
Additional Exercises
Exercise 8.9
Conference abstracts need not follow the move structure in figure 8.1 to accomplish their purpose. Consider, for example, the abstract in excerpt 8L below.
a. How do the moves in excerpt 8L compare to the moves presented in figure 8.1?
Identify the moves in the abstract and their order.
b. Rewrite the abstract so that it (1) begins by introducing the topic, (2) suggests
a gap, and (3) describes the work to be presented.
c. Suggest a title.
Excerpt 8L (from Phares, 2007)
The performance of an inlet for the size-resolved collection of aerosols is presented.
The device resembles a cylindrical differential mobility analyzer (DMA) in that a
sample flow is introduced around the periphery of the annulus between two concentric
cylinders, and charged particles migrate inward towards the inner cylinder in the presence of a radial electric field. Instead of being transmitted to an outlet flow, the sample
is collected onto a Nichrome fi lament located on the inner cylinder. The primary benefit of this mode of size-resolved sampling, as opposed to aerodynamic separation into
a vacuum, is that chemical ionization of the vapor molecules is feasible. Because there
is no outlet aerosol flow, the collection efficiency is determined by desorption of the
particles from the fi lament, chemical ionization of the vapor, separation in a mobility
drift cell, and continuous measurement of the current produced when the ions impinge
on a Faraday plate.
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The Scientific Poster
Exercise 8.10
Imagine that you are a conference organizer with instructions to accept only
five abstracts. The abstracts in excerpts 8B–8L have been submitted. Which five
abstracts would you select? Explain your answer. Give reasons both for accepting
and rejecting the abstracts.
Exercise 8.11
Reflect on what you have learned about writing a conference abstract and title.
Select one of the reflection tasks below and write a thoughtful and thorough
response:
a. Reflect on the different ways in which conference abstracts are organized.
■
■
■
Why does so much variation in the move structure exist? Would there be
any advantages to a more rigid organizational template? Explain.
Does the flexibility that exists make it easier or more difficult to write an
abstract? Explain.
Do any of the variations in excerpts 8B–8L have a greater appeal to you?
Explain.
b. Reflect on the different purposes for a conference abstract and their impact
on the writing process.
■
■
■
Does the fact that the abstract is evaluated by external reviewers make it
easier or more difficult to write? Explain.
Does the fact that the abstract will endure years beyond the conference, in
conference proceedings, add a level of seriousness to the task? Explain.
Should the fact that the abstract will draw interested conference attendees
to your presentation influence the way you write your abstract? Explain.
c. Reflect on your experience writing your own conference abstract and title.
■
■
■
What challenges did you encounter? How did you resolve those
challenges?
What parts of this chapter have helped you the most in writing your
abstract and title? How did you use chapter information to assist you in
your writing?
What have you learned from the experience of writing your conference
abstract and title that will help you the most in the future?
Writing the Conference Abstract and Title
291
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9
Writing the Poster Text
At chemistry conferences, poster sessions are nearly always
more engaging than talks. As proof, consider how few people fall
asleep while viewing a poster! This is because the poster, by its
very nature, is interactive, inviting people in to talk with you about
your science.
Congratulations! If you are reading this chapter, you are likely preparing a poster
for a scientific conference. This means that your conference abstract (chapter 8)
was accepted and that you have been invited to give a poster presentation. In
this chapter, we focus on the various sections of the poster and how to write
them. In chapter 10, we highlight the visual attributes of the poster (layout, font
size, color schemes, etc.). By the end of this chapter, you will be able to do the
following:
■
Address the correct audience in your poster
■
Write the major sections of your poster
■
Use bulleted lists and graphics appropriately
■
Add title, references, and acknowledgments to your poster
As you work through the chapter, you will compose the text and graphics for your
own poster. The Writing on Your Own tasks throughout this chapter guide you
step by step as you do the following:
9A Prepare to write
9B Draft your poster Methods section
9C Draft your poster Results section
9D Draft your poster Discussion section
9E Draft your poster Introduction section
9F Add your poster title, author list, acknowledgments, and references
Reading and Analyzing Writing
We begin by asking you to read and analyze a poster that we created based on
the journal article by Vesely et al. (2003) regarding aldehydes in beer (figure 9.1).
Journal articles usually include far too much information for a single poster;
hence, in the poster in figure 9.1, we include only a fraction of the information
presented in the full journal article. (For the full article, see excerpts 3A, 4A, 6A,
and 7A.) The hypothetical poster focuses on what Vesely’s group might have
presented early in their research project, specifically, the methods that they
developed to analyze their samples. A black-and-white version of the poster is
presented in figure 9.1; a full-color version of the poster is available on the Write
Like a Chemist Web site. Exercise 9.1 guides you in the analysis of the poster and
lays the groundwork for the rest of the chapter.
Exercise 9.1
Browse through the poster in figure 9.1 and answer the following questions:
a. How much content is included in the poster? To answer this question, read
the poster in two minutes and then (without looking at the poster again) jot
down two or three ideas that you have learned. Use this task to generalize
how much information you should include in a poster.
b. Identify the major sections of the poster and the headings and subheadings
that are used to signal these sections. What types of information are included
(and excluded) in each section?
c. What writing conventions predominate in the poster? Examine, for example,
the formatting of headings and lists, capitalization, units, abbreviations,
references, and citations.
d. What audience is targeted in the poster? (There may be more than one.)
Analyzing Audience and Purpose
To benefit most from a poster presentation, you should consider it
primarily an opportunity for an exchange of ideas and dialogue, rather
than merely a forum for data presentation.
—Anholt (1994)
There is no one right audience to target in a poster; rather, the correct audience
will vary with the conference. Some conferences are primarily for experts; others,
such as the national meeting of the American Chemical Society, attract a wide
range of individuals, from high school teachers and undergraduate students to
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The Scientific Poster
Figure 9.1 A poster created from the content in Vesely et al., 2003.
research professors and Nobel Laureates. Sometimes the title of the conference
suggests the predominant audience. For example, a conference titled “Colloidal,
Macromolecular, and Polyelectrolyte Solutions” is likely for experts, whereas a
conference titled “The National Conference on Undergraduate Research” is clearly
for college students. Most conferences send presenters a list of poster guidelines,
and information about audience is often addressed in those guidelines.
Poster Audience
The audience for a poster depends on the conference. Some conferences are more
specialized than others.
In general, however, it is best to assume that your audience knows little about your
topic.
If, after reviewing the conference title and poster guidelines, you are still unsure
about the correct audience for your poster, it is best to target a scientific audience
(e.g., graduate students, faculty, or professionals who are in a different discipline
or subfield of chemistry). Don’t assume that most viewers will be knowledgeable
about your research area; more than likely, only a few will have such specialized
knowledge. Thus, prepare your poster for your most probable audience: chemists
and chemistry students with a research emphasis different from yours. If viewers
want more information, they can ask you questions. Your thoughtful answers to
these questions will satisfy their need for more information. Indeed, the best part
of poster sessions is the exchange of ideas that takes place when passersby stop
and ask you questions about your work.
Exercise 9.2
Based on the titles of the following conferences, indicate which audience(s) should
be targeted: student, scientific, or expert.
a. Great Lakes College Chemistry Conference (GLCCC)
b. Annual Conference on Analytical Chemistry and Spectroscopy
c. The 18th International Symposium on Supercritical Fluid Chromatography
and Extraction
d. National Undergraduate Chemistry Conference
e. The 26th International Conference on Molten Salt Chemistry & Technology
f. The 21st International Symposium on the Organic Chemistry of Sulfur
g. The 16th Annual Chemistry and Biochemistry Graduate Research
Symposium
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The Scientific Poster
Exercise 9.3
Search the Internet for three conferences that would be appropriate for your
research area (or area of interest). Try to find conferences that have different target
audiences (student, scientific, or expert).
9A Writing on Your Own: Prepare To Write
To make sure that you are prepared to create your poster, think about the research that you
have completed so far. What do you want your audience to know after they have viewed
your poster?
Analyzing Organization
Many people believe scientists do not need to learn writing skills. I would
argue that scientists need these skills more than most professions. Concise,
informative, flowing, and intelligent verse can make the difference
between a funded and rejected grant, a published and rejected scientific
publication, or a well-received and botched poster. Writing skills are not
only encouraged, they are mandatory for success in all scientific fields.
—Bradley F. Schwartz, Southern Illinois University School of Medicine
The poster text is divided into the same general IMRD sections as the journal
article: Introduction, Methods, Results, and Discussion. Similarly, most posters
include an Acknowledgments section, some have an abbreviated References section, and all have a title and author list. Most posters do not include an abstract, in
part because of space limitations and in part because an abstract already appears
in the conference proceedings. Like the journal article, the IMRD structure of the
poster follows an hourglass shape. The top (Introduction) and bottom (Discussion)
sections have a broader focus, while the middle sections (Methods and Results)
have a narrower focus. Each section of the poster can be divided into individual
“moves” or steps that guide viewers in a conventional way through the content of
each section. These moves are analyzed in the next part of the chapter.
Analyzing Excerpts
We now read and analyze excerpts from each major section of the poster, beginning with Methods (the section that you are most likely to prepare first) and continuing through the Results, Discussion, and Introduction. The title and author
Writing the Poster Text
297
list, also major sections of the poster, are addressed in chapter 8. Toward the
end of the chapter, we address two less prominent sections: Acknowledgments
and References. Because posters are not published, we cannot include excerpts
from the literature; instead, we present excerpts that we have created based on
three journal articles from module 1: Llompart et al. (2001), Vesely et al. (2003),
and Boesten et al. (2001). For each poster section, you will examine its move
structure, read and analyze the hypothetical excerpts, and review general writing
practices.
The Poster Methods Section
A poster cannot communicate as much information as a journal article
can. When designing a poster, the presenter should accept this constraint
and limit the poster to the essential information. If too much information
is included, the poster will overwhelm the audience and in many cases
cause passersby to give up on that poster and move on to the next one.
—Alley (2003)
The poster Methods section offers a brief snapshot of the methods used in the presented work. (Of course, the Methods section will be more involved if the poster
focuses on the development of a new method or procedure.) The essential moves
of the Methods section are presented in figure 9.2. First materials and then methods are presented. The term “materials” is used loosely and refers to chemicals,
solvents, standards, samples, and so forth. Similarly, the term “methods” refers to
instrumentation, experimental methods, and/or numerical procedures. Because
materials and methods are rather specialized, this section targets a relatively
narrow audience.
Note that the moves in figure 9.2 are characterized by the words highlight,
summarize, and identify. These words emphasize the importance of brevity in
1. Highlight Essential or Novel Materials
(e.g, chemicals, reagents, samples)
2. Summarize Essential or Novel Methods
Identify major
instrumentation
Identify experimental
and/or numerical
procedures
Figure 9.2 A visual representation of the move structure for a
typical poster Methods section.
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The Scientific Poster
the poster Methods section. The average person will likely view your poster for
only a few minutes. Complex experimental procedures are too difficult to grasp
in such a short time. Instead, focus only on the key steps used to obtain the
information presented in the poster. If more details are needed, viewers can ask
for them.
With these two moves in mind, we examine the Methods sections of three
hypothetical posters. The first poster concerns the detection of PCBs in full-fat
milk. We include both the poster Methods section (excerpt 9A) and the journal
article Methods section (excerpt 9B). In this way, you can see for yourself the
differences and similarities between the two genres. A key difference is that the
poster includes far less information than the journal article. For example, the
poster addresses only full-fat and skim milk, whereas the journal article also
includes half-fat milk. Half-fat milk is an intermediate case and serves only
to confirm the two extreme cases. Thus, the intermediate case can be omitted
without changing the essential message of the poster.
Exercise 9.4
Compare excerpts 9A and 9B. What similarities and differences do you notice?
Consider science content, organization, and writing conventions (e.g., subheadings, capitalization, abbreviations, and parentheses).
Excerpt 9A (a poster Methods section based on Llompart et al., 2001)
METHODS
Reagents and Materials
■
CI
Full-fat (3.61%) and skim milk (0.34%) samples were obtained from local supermarkets and spiked with one of eight PCB congeners (1–100 ng/mL).
CI
CI
CI CI
CI
CI
CI
CI
PCB-28
CI
CI
CI
CI
PCB-118
■
PCB-101
CI
CI CI
CI
CI
PCB-138
CI
CI
CI
CI
CI
CI
PCB-52
CI
CI
CI
CI
CI
CI
PCB-105
CI
CI
CI
CI
CI
PCB-153
CI
CI
CI
CI
CI
CI
PCB-180
Spiked samples were homogenized, held at 4 C for 24 h, frozen, then thawed 1 h
before analysis.
Writing the Poster Text
299
■
SPME holders with one of two fiber assemblies were used:
100 μm PDMS (poly(dimethylsiloxane))
65 μm PDMS-DVB (poly(dimethylsiloxane)divinylbenzene)
Saponification and HSSPME Procedures
■
PCB-spiked milk samples were placed in headspace vials. When saponification was
performed, samples were treated with NaOH, sealed, immersed in water (100 C),
and equilibrated for 6 min.
■
During HSSPME, the fiber was exposed to the headspace over the sample for 5–240
min as the sample was stirred.
Sample Analysis
■
PDMS-fibers were analyzed by GC-electron capture detection using an HP 5890
series II GC.
■
PDMS-DVB fibers were analyzed by GC/MS-MS using a Varian 3800 GC with ion
trap (Varian Saturn 2000).
Abbreviations in Posters
Most abbreviations are defined at first use in posters. In excerpt 9A:
PDMS is first used and defined in the Methods section.
PCB is first used and defined in the Introduction, thus does not need to be defined
again.
Excerpt 9B (adapted from Llompart et al., 2001)
Experimental Section
Reagents and Materials. The PCB congeners, 2,4,4-trichlorobiphenyl (PCB-28),
2,2,5,5-tetrachlorobiphenyl (PCB-52), 2,2,4,5,5-pentachlorobiphenyl (PCB-101),
2,3,3,4,4-pentachlorobiphenyl (PCB-105), 2,3,4,4,5-pentachloro-biphenyl (PCB-118),
2,2,3,4,4,5-hexachlorobiphenyl (PCB-138), 2,2,3,4,4,5-hexachlorobiphenyl (PCB-153),
and 2,2,3,4,4,5,5-heptachlorobiphenyl (PCB-180) (PCB numbering according to
IUPAC) were supplied by Ultra Scientific (North Kingstown, RI). Isooctane, acetone,
and sodium hydroxide were obtained from Merck (Mollet del Valles, Barcelona, Spain).
All the solvents and reagents were analytical grade.
Isooctane, acetone, and sodium hydroxide were obtained from Merck (Mollet del
Valles, Barcelona, Spain). All the solvents and reagents were analytical grade.
The full-fat milk (3.61% fat), half-fat milk (1.55% fat), and skimmed milk (0.34%
fat) were purchased from local supermarkets. Spiked milk samples were prepared by
addition of a small volume of acetone solutions containing the target analytes in the
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The Scientific Poster
concentration range of 1–100 ng/mL. The spiked samples were homogenized in an
ultrasonic bath for 5 min; later, the samples were kept at 4 C for 24 h, to allow analyte–
matrix interactions. Afterward, they were frozen at –20 C until 1 h before the analysis.
The certified reference material (CRM 450), used for the validation of the method, is
real contaminated powdered milk with a certified content in PCB-52, PCB-101, PCB-118,
PCB-156, and PCB-180. This material contains approximately 3.9% water and 25%
fat. It is used after reconstituting and was supplied by the EC Community Bureau of
Reference (BCR).
HSSPME Extraction Procedure. Manual SPME holders were used with a 100-μm
poly(dimethylsiloxane) (PDMS) and 65-μm poly(dimethylsiloxane)-divinylbenzene
(PDMS-DVB) fiber assembly (Supelco, Bellefonte, PA). The fibers were conditioned as
recommended by the manufacturer.
The samples were placed in headspace vials. When saponification was performed, a
few milliliters of NaOH solution were added to the sample. The vial was sealed with a
headspace aluminum cap furnished with a Teflon-faced septum, immersed in a water
bath maintained at 100 C, and let equilibrate for 6 min before HSSPME. Afterward,
the fiber was exposed to the headspace over the sample for 5–240 min, depending
on the experiment. The sample was magnetically agitated during sampling. Once
the exposition period was fi nished, the fiber was immediately inserted into the GC
injector and the chromatographic analysis was carried out. Desorption time was
set at 5 min.
Chromatographic Conditions. GC-ECD analyses were performed in an HP 5890
series II GC equipped with an electron capture detector and a split/splitless injector,
operated by an HP Chemstation software. PCBs were separated on a 25 m length 0.32
mm i.d., HP-1 column coated with a 0.17 μm film. The GC oven temperature program
was as follows: 90 C hold 2 min, rate 20 C/min to 170 C, hold for 7.5 min, rate 3 C/min,
to final temperature 280 C, and hold for 5 min. N2 was employed as carrier and makeup
gas, with a column flow of 1.2 mL/min at 90 C. Split flow was set at 50 mL/min.
Injector and ECD temperatures were 260 and 280 C, respectively. Injector valve time
was set at 2 min.
The GC/MS-MS analyses were performed on a Varian 3800 gas chromatograph
(Varian Chromatography Systems, Walnut Creek, CA) equipped with a 1079 split/splitless injector and a ion trap spectrometer (Varian Saturn 2000, Varian Chromatography
Systems) with a waveboard for MS-MS analysis. The system was operated by Saturn
GC/MS WorkStation v5.4 software. The MS-MS detection method was adapted from
elsewhere.29 PCBs were separated on a 25 m length 0.32 mm i.d., CPSil-8 column
coated with a 0.25 μm fi lm. The GC oven temperature program was as follows: 90 C
hold 2 min, rate 30 C/min to 170 C, hold for 10 min, rate 3 C/min to 250 C, rate 20
C/min to a fi nal temperature of 280 C, and hold for 5 min. Helium was employed as
a carrier gas, with a constant column flow of 1.0 mL/min. Injector was programmed
to return to the split mode after 2 min from the beginning of a run. Split flow was set
at 50 mL/min. Injector temperature was held constant at 270 C. Trap temperatures,
manifold temperatures, and transfer line temperatures were 250, 50, and 280 C,
respectively.
Writing the Poster Text
301
Respectively
See appendix A.
Even at first glance, several differences and similarities are apparent between
the poster and journal article excerpts. Consider the fi rst move. Both the
poster and journal article begin by presenting materials (chemicals, samples, reagents, etc.), and both use subheadings to signal this move. In the
poster, however, the PCBs are identified by chemical structure rather than by
chemical name. Structures, although not required, are easier to grasp at a
glance, enhancing the audience’s ability to understand the compounds quickly.
Note, too, that product information (vendor, purity) is not included in the
poster (although this information may be included if deemed essential by the
authors).
Differences are apparent in the second move as well. Both the poster and
journal article signal the second move with subheadings, but in the poster, the
procedures are presented in bulleted lists of sentences or phrases. Such lists,
which could also be numbered, are common in posters. Essential details are presented, specifically those that are needed to understand the rest of the poster. In
this case, we chose to highlight a few details about the saponification and extraction procedures. Note, however, that we did not include operating parameters
for the GC-electron capture or GC/MS-MS instruments (other than the vendors
and model numbers). In a poster, such parameters are optional; they may be
included, but they are not required. Also, in a poster (but not a journal article),
the parameters can be listed in phrases rather than in complete sentences. An
illustrative sketch, diagram, or photograph of the SPME holder, fiber, or extraction setup would also be appropriate to include at this point. Finally, if any
numerical methods have been used, they should be mentioned in an additional
bullet.
As a second example, we present another poster Methods section (excerpt 9C)
based on the same research presented in figure 9.1. Recall that the hypothetical
poster in figure 9.1 focuses on methods development; the poster in excerpt 9C
focuses on methods application. If you examine the Methods sections in the two
posters, you will see that figure 9.1 describes how the on-fiber derivatization procedure was optimized; excerpt 9C describes how the optimized procedure was
used to analyze beer samples.
Learning how to focus on specific aspects of your work is an important skill in poster
preparation.
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The Scientific Poster
Exercise 9.5
Compare the Methods section of the poster in figure 9.1 with the Methods section
in excerpt 9C. What similarities and differences do you notice? Consider science
content, organization, and writing conventions (e.g., subheadings, capitalization,
abbreviations, and parentheses).
Excerpt 9C (a poster Methods section based on Vesely et al., 2003)
METHODS
Samples
■
The beer samples (American lagers) were stored at 30 C for 4, 8, or 12 weeks.
■
The controls were stored at 0 C for 12 weeks.
Methods Validation
■
Calibration curves were prepared for 9 aldehydes (linearity 0.96).
■
Each beer sample was measured 10 times (variance
■
Recovery was determined by spiking beer samples with 10 ppb of the standard
aldehyde (recoveries 89–110%).
5.5%).
On-Fiber Derivatization and Detection of Aldehydes
■
The derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA)
was absorbed onto a 65 μm PDMS/DVB SPME fiber (10 min, 50 C).
■
The fiber was placed in the sample headspace (50 C, 60 min).
■
The beer aldehydes selectively reacted with the PFBOA in the fiber.
■
The oximes that formed were desorbed and detected by GC/MS (DB-5 30 m 0.25 mm 0.50 μm; He carrier gas at 1.1 mL/min; splitless, injector 250 C).
Bulleted Lists
■
Start full sentences with a capital letter and end them with a period.
■
Start sentence fragments with either a capital or lowercase letter; a period is not
needed.
■
If possible, use one list style consistently within a poster.
As the last example, we present a poster Methods section based on Boesten
et al. (2001) concerning the asymmetric Strecker synthesis of an -amino acid
(excerpt 9D and at the end of chapter 2). The poster Methods section presents only
Writing the Poster Text
303
part of the content from the article because (once again) the full content would be
too much for a poster. The poster focuses on only the first step of the synthesis:
the asymmetric Strecker reaction of (R)-phenylglycine amide 1 and pivaldehyde 2
to preferentially crystallize the (R,S) amino nitrile product 3. The poster Methods
section includes relevant general information and the optimized steps used in the
synthesis of (R,S)-3. (In the Results section of this poster, the authors explain how
these steps were optimized.) An equation is used to illustrate the general reaction,
introduce the compounds and their compound labels, and identify the reaction
variables (solvent, time, temperature). The steps of the synthesis are summarized
in a bulleted list following the equation.
Excerpt 9D (a poster Methods section based on Boesten et al., 2001)
EXPERIMENTAL SECTION
General. (R)-Phenylglycine amide 1 was purchased from DSM (Netherlands). The dr of
(R,S)-3 and (R,R)-3 was determined by 1H NMR using the relative integration between
the t-Bu signals at 1.05 ppm for (R,S)-3 and 1.15 ppm for (R,R)-3. NMR spectra were
recorded using a Varian VXR-300 spectrometer (300 mHz) and referenced to residual
solvent.
The synthesis of amino nitrile (R,S)-3
Ph
O
Ph
NaCN, HOAc
+
H2N
H
CONH2
(R)-1
2
solvent, time, temp
HN
H
Ph
CONH2
CN
(R,S)-3
CONH2
HN
+
H
CN
(R,R)-3
■
A stirred suspension of 1 (400 mmol) in H2O (400 mL) was added to pivaldehyde 2
(419 mmol) and stirred for 30 min.
■
NaCN/HOAc was added at 23–28 C. The mixture was heated to 70 C and stirred
for 24 h.
■
After cooling to 30 C, the product was filtered, washed (500 mL H 2O), dried, and
analyzed by 1H NMR.
■
(R,S)-3 formed as a colorless solid (92.4%, dr 99/1).
Exercise 9.6
Review excerpts 9A–9D. Based on these excerpts, answer the following questions:
a. What information is generally included in the Methods sections of posters?
What information is typically excluded?
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b. What conclusions can you draw about the audience that is targeted in the
Methods section of a poster?
c. How well does each poster excerpt follow the move structure in figure 9.2?
Writing conventions typical of a poster Methods section are summarized below.
Many of these conventions apply to other sections of the poster, as well.
■
Abbreviations: Abbreviations are usually defi ned in parentheses at their first
use, for example, “pentafluorobenzene (PFB)”. Readily understood symbols or abbreviations may be used without definition (e.g., GC/MS, MeOH,
R-OH, Pgas, cat.). A few unconventional abbreviations may be used in posters
if space is tight (e.g., “temp” for “temperature,” “rt” for “room temperature,”
“wk” for “week,” “exp” for “experiment,” “sat’d” for “saturated,” “&” for
“and”). Additionally, some abbreviations, such as those for long chemical
names, need not be defined if an exact identity is not essential for understanding the poster.
Be careful, however, not to become too casual with abbreviations. For
example, popular shorthand is not appropriate (e.g., “B4” for “before” or
“FYI” for “for your information”). Also, use abbreviations consistently
throughout the poster. For example, “eq” should not be used for “equation”
and “equivalent” in the same poster.
■
Bulleted or numerical lists: Lists are common in posters. It is customary to
capitalize the first letter of the first word in a bulleted list if the list contains
full sentences ending with periods; lowercase is preferred for lists of phrases
or fragments (not ending with periods). When possible, use the same types
of lists (bulleted or numbered) throughout your poster. (See comments on
parallelism below for related issues.)
■
Capitalization: Molecular formulas (NaOH), abbreviations (PCBs), instrument
vendors (Varian 3800 GC), and chemical compounds (e.g., “2-methylpropanal”)
are capitalized as recommended in The ACS Style Guide.
■
Numbers and units: Conventional scientific units should be used in poster
Methods sections (mL, μm, mol, M, etc.); however, some formatting conventions may be relaxed. For example, the conventional space between a number
and its unit may be omitted in a poster, and the numerical form of a number
may be used instead of its word form (even at the start of a sentence). If space
allows, however, follow conventional practices. One convention that should
never be relaxed is the use of leading zeros for numbers 1 (e.g., use 0.35
not .35).
Conventional formatting
Relaxed formatting
Writing the Poster Text
2 μL, nine aldehydes, 30 m 0.25 mm
2μL, 9 aldehydes, 30 m 0.25 mm
305
■
Parallelism: Parallel language should be used in bulleted lists in poster
Methods sections and elsewhere. Not only is parallelism grammatically correct, but its repetitive pattern also helps viewers comprehend poster information more quickly. Pay particular attention to parallel subheadings and lists:
Nonparallel list
1. American lager samples were stored . . .
2. Load PFBOA on fiber . . .
3. Concentration of aldehydes on . . .
Parallel list
1. American lager samples were stored . . .
2. PFBOA was loaded on fiber . . .
3. Aldehydes were concentrated on . . .
Nonparallel subheadings Chemicals
Extracting the Filters
Analyze using GC
Parallel subheadings
Chemicals
Extraction Procedure
GC Analysis
■
Verb tense: Poster Methods sections are written predominantly in the past
tense (e.g., used, exposed, inserted, were stored) because they describe work
done in the past.
■
Voice and we: Poster Methods sections are written largely in passive voice;
active voice is used less often. We is commonly avoided.
Passive voice Aldehydes were concentrated and derivatized . . .
(R)-Phenylglycine amide 1 was purchased from DSM.
Active voice PFBOA was the derivatizing agent.
Unconventional Abbreviations
Some unconventional abbreviations are allowed in posters (e.g., “temp” for “temperature”).
However, shorthand (e.g., “B4” for “before”) should not be used.
Capitalization
See appendix A.
Numbers and Units
See appendix A.
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The Scientific Poster
Parallelism and Fragments
Bulleted fragments often replace complete sentences in posters. No period is needed after
a fragment. When possible, use parallel language in lists and headings. (See appendix A.)
Exercise 9.7
Reconsider poster excerpts 9A, 9C, and 9D and complete the following tasks:
a. Make a list of the abbreviations used in each poster. Which abbreviations
do you think were defined earlier in these posters (e.g., in the Introduction
section)? Which will most likely not be defined at all?
b. Examine the lists contained in each poster. Are all items in a single list parallel to each other? Are punctuation and capitalization used consistently?
c. Is past or present tense preferred? Is passive or active voice preferred?
Support your answer with at least three examples.
Exercise 9.8
When poster excerpts 9A, 9C, and 9D were prepared, it was assumed that we had
plenty of space. However, assume now that space is tight. Conserve space in the
first list of each poster by doing one or more of the following:
a. Convert the bulleted lists (which currently are written in full sentences) into
shorter fragments. (Be sure to keep the fragments parallel and use proper
punctuation.)
b. Abbreviate words that will be easily understood in their abbreviated forms
(e.g., “temp” for temperature).
c. Reformat numbers and units to make them more condensed (even though
such formatting would be incorrect in a journal article).
d. Omit some information or make the writing more concise.
Exercise 9.9
Consider the following excerpts taken from experimental sections of journal
articles. Convert each procedure into a single item or a bulleted list of items that
would be appropriate for a poster Methods section. Omit information that would
not be included in a poster.
a. FTIR spectra were recorded using a Nicolet model 870 spectrometer (Madison,
WI) equipped with a deuterated tryiglycine sulfate (DTGS) detector. (From
Kizil et al., 2002)
Writing the Poster Text
307
b. The liquid chromatograph (LC) was an Agilent (Waldbronn, Germany) 1100
series system consisting of vacuum degasser, autosampler, binary pump,
column oven, and diode array detector. (From Pelander et al., 2003)
c. 2-(p-Toluenesulfonyl)-4-methoxyacetophenone (2a). A mixture of 2bromo-4-methoxyacetophenone (45.8 g, 200 mmol) and p-toluenesulfinic
acid sodium hydrate (35.6 g, 200 mmol) in ethanol (1 L) was heated at
reflux for 1.5 h. The mixture was stirred and cooled to room temperature,
and the resulting solid was collected, washed with ethanol (2 50 mL), and
dried to give 54.6 g (90%) of pure 2a. (Adapted from Swenson et al., 2002)
d. Delphinium cultorum cv. Magic Fountains dark blue/white bee seeds were
donated by Bodger Seed, Ltd., South El Monte, CA. The seeds were germinated
in high porosity, peat-based growing mix in Styrofoam trays (4 in. 6 in. 2 in.) and grown until the first leaf appeared. The seedlings were then transplanted into pots (4 in. 4 in. 6 in.) and then into large clay pots (10 in. 6 in. 10 in.) and were grown until maturity. The plants were raised in the
Bioactive Natural Products Laboratory Greenhouses, Michigan State University.
The plants were subjected to a 12 h photoperiod, watered once daily, and maintained at 75 F. Plant parts were harvested when 75–80% of the florets were
fully expanded on each raceme and stored at –20 C. (From Miles et al., 2000)
9B Writing on Your Own: Draft Your Poster Methods Section
Create a list of the steps that you took in your research. Which of these steps are necessary
to include in your poster? Which can be excluded?
Consult figure 9.2 to review the moves that make up the Methods section of a poster.
After you have decided what to include (and what to exclude), write the Methods section
of your poster. Remember that past tense is preferred and that bulleted lists (with parallel
language) are common. Use standard formatting, number, and abbreviation conventions
at first; convert to abbreviated formats if space is tight. Consider adding a photograph or
illustration to your Methods section.
The Poster Results Section
Like any scientific presentation, the poster should tell a story. . . . Include
only materials relevant to the story line.
—Anholt (1994)
The Results section is undoubtedly the most important section of the poster. The
chance to share your results with others is the predominant reason for preparing
your poster in the first place. However, you must be careful not to overwhelm
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The Scientific Poster
your readers by presenting too many results. Focus on one or two key findings,
targeting a reasonably narrow audience (hence, the narrow part of the hourglass).
Avoid the temptation to crowd too much information into a single poster. Limit
yourself to results that can be digested in just a few minutes. Deciding which
results to include (and which to exclude) is one of the most challenging steps in
preparing a poster.
Note that “raw” data (e.g., spreadsheet calculations, uncalibrated measurements, original spectra before they have been baseline corrected) should not be
included in a poster. It is important that you present results only after they have
been carefully analyzed and prepared for public view.
Most results in posters are presented in graphical form (e.g., figures, graphs,
photographs, schemes, illustrations, spectra). Graphics are preferred over text
because they allow the reader to comprehend the data more quickly (provided the
authors do not overcrowd their graphics). The text accompanying the graphics
serves largely to guide viewers through the data. In general, figures are preferred
over tables because they are easier to read and understand at a glance; however,
tables may be included if they provide useful information and/or illustrate important trends.
As you prepare your Results section, imagine “walking” someone through your
poster. Your results should be organized so that they guide viewers through your
story of scientific discovery. (Like the journal article, a poster should also tell a
story.) The moves for the poster Results section (figure 9.3) are designed to facilitate this process. In move 1, you set the stage and prepare viewers for moves 2 and
1. Share Preliminary Results
Prepare viewers for principal findings by doing one or more of the following:
Share results that
build confidence in
your approach
Share results that
motivated your
study
Share results that
lay groundwork for
your principal
findings
2. Share Principal Results
(i.e., share key findings; identify and summarize key trends)
3. Share Related Results (optional)
(i.e., share results that support, extend, or strengthen your principal findings)
Figure 9.3 A visual representation of the move structure for a typical poster Results
section.
Writing the Poster Text
309
3 by presenting preliminary results, that is, results that lead toward your principal findings (move 2). Preliminary results can introduce or motivate your claims
(e.g., a spectrum that shows the presence of a pollutant), build confidence in your
measurements (e.g., a calibration curve), or lay groundwork needed to understand
your principal findings (e.g., a chromatogram that illustrates how a complex mixture was separated). As you prepare move 1, imagine yourself pointing to your
poster and saying to your viewers “First, we wanted to be sure we could do ____”,
“In previous work, we successfully prepared ____”, or “This spectrum confirmed
that ____ is present in our sample.” By preparing your viewers for what lies ahead,
you strengthen their confidence in themselves (to understand your results) and in
you (to present data that they can trust).
Walking Viewers through a Poster
At most conferences, there is a 2 h block of time when you are expected to stand by
your poster. That time allows you to “walk” viewers through your poster and engage
in dialog.
After the foundations are laid (move 1), you are ready to share principal findings (move 2). Using two to four graphics (and accompanying text), focus your
viewers’ attention on only the most important results. In posters, these results
can report what has already succeeded or what has yet to succeed. Use graphics
to display the trends visually, and use text to highlight and summarize those
trends. Label relevant peaks and features in your figures to draw your viewers’
attention to the most important areas. (This is like using a pointer in a slide show
presentation.) These labels will make your key findings more conspicuous. As in
journal articles, poster figures include captions, placed either below or to the side
of the figures. Unlike figures in journal articles, poster figures may also include
titles above them.
Poster Figures
In journal articles, figures have captions but no titles. In posters, figures often use captions,
titles, and other descriptive labels to highlight important points.
Some poster Results sections conclude with move 2 (which is fi ne), but in
many posters, authors share additional results. Move 3 allows you to do this
without overwhelming your viewers. The key is to relate these results to your
principal findings. Viewers will more easily grasp a second set of data if it supports, extends, or strengthens what they have just learned.
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The Scientific Poster
To summarize, as you prepare your Results section, divide your results into
three groups: (1) preliminary results, (2) principal results, and (3) related results.
Share preliminary results first (move 1), principal results second (move 2), and
related results third (move 3). How you categorize your results is your decision;
what is important is the logical thread connecting all the data that you share.
Viewers will be able to absorb more information if the data build on themselves
in a logical manner.
Let’s examine these moves in three hypothetical poster Results sections. We
begin with excerpt 9E, the poster about PCBs in milk. The authors present their
results in four steps, walking the reader through a story that might be titled
“Detecting PCBs: Before and After Saponification.” The steps are numbered,
rather than bulleted, to make the sequencing clear. First, preliminary results
are presented, highlighting what happens before saponification. The data are
presented in two chromatograms (Figure 1). The first chromatogram shows
PCBs detected in skim milk; the second, in full-fat milk. (Both samples were
spiked with equal amounts of PCBs.) Side by side, these two chromatograms
make the problem clear: PCBs are more difficult to detect in full-fat milk
because of matrix effects (i.e., the extra fat in full-fat milk retains the PCBs).
Such results develop the viewer’s confidence in the data (e.g., without the skim
milk chromatogram, viewers might think that the problem is a poorly operating GC). The data also prepare viewers for similar graphs later on in the
poster. The accompanying text helps focus the viewer’s attention on the relevant
information.
Principal results (move 2) are presented in steps 2 and 3. In step 2, the authors
describe the saponification process, which involves the optimization of five reaction conditions. These conditions are listed in a table for easy viewing (Table 1).
In step 3, the success of the technique is showcased with an “after saponification”
chromatogram of PCBs in full-fat milk (Figure 2). Because the groundwork was
laid in Figure 1 (“before saponification”), the viewer is prepared to understand
and appreciate the importance of this chromatogram. The essential result is highlighted in the text, that saponification increased the PCB sensitivity in full-fat
milk by a factor of 4 to 8 (depending on the PCB congener).
Poster Tables
See chapter 16 for table formatting.
The results are extended (move 3) in step 4, “Procedure Validation.” The
extended information informs the viewer that (1) results were linear and reproducible and (2) the technique also works with a certified reference standard
(Table 2). These results build logically on the principal finding of the work, that
with saponification PCBs can be detected in full-fat milk.
Writing the Poster Text
311
Excerpt 9E (a poster Results section based on Llompart et al., 2001)
RESULTS
1. Before saponification. PCBs were detected in skim milk (Fig. 1A) but not
full-fat milk (Fig. 1B) because of matrix effects in full-fat milk.
(A)
(B)
Figure 1. PCBs in spiked skim milk (A) and spiked full-fat milk (B).
2. Saponification. Extraction of PCBs from full-fat milk matrix was improved
by saponification (Table 1).
Table 1. Optimization of saponification process.
Factor
Options Tried
Best Option
NaOH vol (mL)
NaOH conc. (%)
Time (min)
Fiber
Stirring
0.5, 2.0, 3.5
20, 30
30, 60
PDMS, PDMS-DVB
yes, no
2.0–3.5
20
60a
PDMS-PVB
yes
a
312
Longer times were better but too slow for desired approach.
The Scientific Poster
3. After Saponification. Skim milk response increased 5 to 10 times;
full-fat milk response increased 4 to 8 times, depending on PCB
congener (Fig. 2).
Figure 2. PCBs in full-fat milk with saponification.
4. Procedure Validation. Calibration results were linear (R 2 0.994) and
reproducible (RSD 11.0 %) over a wide range of concentrations. Recoveries
75% were achieved with a certified milk sample (Table 2).
Table 2. Procedure validation with certified milk (25% fat).
PCB
Certified Value (ng/g)
Recovery (%)
52
1.16 0.17
75
118
3.19 0.24
97
153
8.60 1.10
98
156
1.64 0.11
102
180
9.29 0.26
88
We next consider the two posters concerning aldehydes in beer, the first on
methods development and the second on methods application. In particular,
note what information is included in each Results section. In the poster in figure 9.1,
the optimization of temperature and time comprises the bulk of the Results
Writing the Poster Text
313
section. In the second poster, these “results” have been moved to a single bulleted item in the Methods section (excerpt 9C), which states simply that “The
fiber was placed in the sample headspace (60 min, 50 C).” The new Results
section (excerpt 9F) focuses on the aldehydes. The authors use two figures to
convince the viewer that the aldehydes can be detected: (1) a chromatogram
showing the retention times of the nine derivatized aldehydes and (2) a mass
spectrum of methional, showing that m/z 181 is a fragment ion that can be used
to detect the aldehydes.
The principal findings are shared in Figure 3. A bar graph summarizes the
concentrations of the nine aldehydes in beer after 4, 8, and 12 weeks of storage.
The graph groups the aldehydes by their most likely source. This grouping will
be useful in the Discussion section of the poster, where the individual aldehydes
are discussed. A graph is preferred over a table for these data because a graph
makes the trends easier to see. The text accompanying the graph reinforces these
trends.
Bar Graphs
In posters, bar graphs are used to illustrate even simple relationships. In journal articles,
such relationships are usually expressed in words.
The authors expand these results in Figure 4; in this case, they elucidate
the relationships between aldehyde concentrations and beer fl avor thresholds. Based only on Figure 3, a viewer might assume that furfural affects beer
fl avor because it increased the most during beer storage. However, as shown
in Figure 4, even at high concentrations, furfural is only a small fraction
of its fl avor threshold (FT). Instead, (E)-2-nonenal has the greatest impact,
although it is still 30% FT. Figure 4 also makes clear the important message that none of the aldehydes in stored beer exceeded their respective fl avor
thresholds.
Excerpt 9F (a poster Results section based on Vesely et al., 2003)
RESULTS
314
■
A beer sample was spiked with 9 aldehydes and derivatized. The chromatogram is
shown in Fig. 1. Aldehydes were detected by m/z 181 (Fig. 2).
■
All aldehydes increased during storage (Fig. 3), but none exceeded their fl avor
threshold (Fig. 4).
The Scientific Poster
■
Fig. 1. Chromatogram of 9 aldehydes in spiked beer. Each aldehyde has an isomer (e.g., 1, 1).
Fig. 2. Aldehydes were identified by m/z 181 (methional shown).
1600
1400
1200
Percent increase
(relative to control)
Heat
exposure
4 weeks
8 weeks
12 weeks
1000
Degradation of
linoleic acids
Degradation of
amino acids
800
600
400
200
fu
rfu
ra
l
)-2
-n
on
en
al
(E
he
xa
na
l
pe
nt
an
al
et
hi
on
al
la
ce
ta
ld
eh
yd
e
m
ph
en
y
2m
2m
et
hy
l
pr
op
an
al
et
hy
lb
ut
an
3al
m
et
hy
lb
ut
an
al
0
Derivatized aldehyde
Fig 3. Increase of aldehydes (grouped by source) during storage.
Percent flavor threshold
30%
20%
10%
Degradation of
linoleic acid
Degradation of amino acids
Heat
exposure
Derivatized aldehyde
Fig. 4. Percent of flavor threshold at 12 weeks for 9 aldehydes.
rfu
fu
en
on
-n
)-2
(E
ra
l
al
l
na
he
xa
nt
an
al
e
ph
en
yl
ac
pe
hy
d
al
et
m
et
de
hi
on
al
al
an
hy
l
bu
t
an
et
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3-
hy
l
et
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2-
2-
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et
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lp
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0%
Exercise 9.10
How is the attention of viewers drawn to important data and trends in excerpt 9F?
Exercise 9.11
In excerpts 9E and 9F, text is limited; the graphics tend to speak for themselves.
Review the excerpts and answer the following questions:
a. What purpose(s) do the graphics and text serve?
b. What general rule of thumb may guide you in finding the right balance
between text and graphics in posters?
Lastly, we consider the Results section for the poster that describes the asymmetric Strecker synthesis (excerpt 9G). The results comprise three bulleted items.
The first item presents evidence that the targeted diastereomer (R,S)-3 can be
verified by X-ray analysis. The second item identifies the reaction conditions
that were optimized (solvent, time, and temperature) and graphs one of them
(time). The principal findings are presented in the third item. The authors share
as their principal findings the reaction conditions that were tried and ultimately
produced (R,S)-3. The results are presented in a table for easy viewing (Table 1).
The optimal conditions are listed (logically) in the last row of the table (in bolded
font) and reiterated in the text. The Results section ends here; no supporting or
extending evidence is included.
Excerpt 9G (a poster Results section based on Boesten et al., 2001)
RESULTS
■
The absolute configuration of (R,S)-3 was confirmed by X-ray analysis (Fig. 1).
Fig. 1. X-ray structure of (R,S)-3.
Writing the Poster Text
317
■
Solvent, time, and temperature were optimized. Time was optimized at 30 min with
dr 99/1 (Fig. 2).
100
95
Percent yield
90
85
80
75
70
65
0
5
10
15
20
25
30
35
Time (min)
Fig. 2. Optimization of reaction time.
■
Optimization trials (Table 1) showed that water at 70 C for 24 h produced (R,S)-3 in
93% yield (dr 99/1).
Table 1. Optimization trials for the synthesis of (R,S)-3.
solvent(s)
temp
(°C)
time
(h)
yield
(%)
dr
(R,S)-3/(R,R)-3
MeOH
rt
20
80
65/35
MeOH/2-PrOH
rt
22
51
99/1
2-PrOH
rt
22
84
88/12
2 PrOH/t-BuOH
rt
20
65
96/4
MeOH/H2O
rt
20
69
81/18
H 2O
55
24
81
85/15
H 2O
60
24
84
96/4
H 2O
65
24
84
98/2
H 2O
70
24
93
99/1
Compound Labels
Standard conventions for using compound labels such as (R,S)-3 should be followed in a
poster. (See appendix A.)
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The Scientific Poster
The writing conventions listed below are commonly used in poster Results
sections.
■
Abbreviations: Due to limited space, the abbreviation “Fig.” may be used to
refer to figures. “Table” is not generally abbreviated. Other readily understood abbreviations may be used when space is tight (e.g., temp, conc,
MeOH).
■
Bulleted or numerical lists: Lists are frequently used when highlighting or
summarizing results. Follow the formatting guidelines presented above in
the discussion of poster Methods sections. When possible, use the same type
of formatting throughout your poster.
■
Graphics and graphics labels: In general, poster graphics follow the same
formatting guidelines as journal articles (see chapter 16). Two differences are
that (1) titles may be used in poster figures (along with captions, which are
required), and (2) color may be used freely in poster graphics (first to illustrate the science but also to add visual appeal). As in journal articles, poster
graphics should be labeled. Table titles are placed above the table. Figure
captions are placed either below or beside the figure. Dangling graphics,
that is, graphics that are never referenced in the text, should be avoided.
Exceptions to this rule are graphics added primarily for visual appeal (e.g.,
a logo, photograph, or clipart). Photographs used to convey science (e.g., a
photograph of an instrument or a map of a sampling site), however, should
be labeled.
■
Verb tense: Poster Results sections use past tense to describe results
obtained in the past and present tense to describe “facts” expected to
be true over time:
Past tense
High sensitivity to PCBs was observed in skim milk. The best
yield was obtained with H2O.
Present tense Each aldehyde produces two peaks in the chromatogram.
Each derivatized aldehyde fragments to give a major peak
at m/z 181.
■
Voice and we: Poster Results sections use both passive and active voice, and
the word we is typically avoided:
Passive voice High sensitivity was achieved (not “we achieved high
sensitivity”).
Five factors were optimized (not “we optimized five factors”).
Active voice Calibration results were linear.
Furfural had the highest concentration.
Writing the Poster Text
319
Dangling Graphics
Graphics that are included in a poster, but are never referenced in the text.
Graphics should not dangle in posters, unless they are included for aesthetic
purposes only.
Tense–Voice Combinations in Results Sections
See table 4.1.
Exercise 9.12
Revisit the graphics in excerpts 9E–9G and answer the following questions:
a. Are the figure captions and table titles placed in conventional places?
b. Do the authors add titles to their figures? If so, where are those titles placed?
c. Are there any dangling graphics in these excerpts? Explain.
Exercise 9.13
Consider the following sets of bulleted items (adapted from Jozefaciuk et al., 2003;
Dellinger et al., 2001; Jozefaciuk et al., 2003; respectively). Which item, in each
set, is most appropriate for a poster Results section? Consider standard tense,
voice, and conciseness practices to make your decision.
Set 1
■
We present the results of water uptake measurements in Figure 1.
■
Results of water uptake measurements are presented in Fig. 1.
Set 2
■
Exposure of the cells to H2O2 (100 μM) produced 100% damaged DNA.
■
Exposure of the cells to 100 μM hydrogen peroxide produced 100% damaged
DNA.
Set 3
320
■
In our work, we found that RAMEB alone absorbed a high amount of water.
■
RAMEB alone absorbed a high amount of water.
The Scientific Poster
Exercise 9.14
Create two bulleted items to accompany the following table (adapted from Plaper
et al., 2002) that would be appropriate for a poster Results section:
Table 1. Uptake of chromium by E. coli cells treated with different Cr3 compounds.
Cr3 compound
CrCl3 6H 2O
Cr(NO3)3 9H2O
KCr(C2O4)2 3H2O
concentration
added (mM)
intracellular uptake of Cr
(mg of Cr/g of dry weight)
0
0.021
0.63
1.8
1.25
6.7
0
0.021
0.63
2.4
1.25
5.7
0
0.025
0.63
0.022
1.25
0.02
9C Writing on Your Own: Draft Your Poster Results Section
Decide what results you are going to present in your poster. Be careful not to include too
many results or to present results that are still in “raw” form. Categorize your results into
three groups according to the move structure in figure 9.3: preliminary, principal, and
related. These groupings will help you organize your results so that they weave a consistent
thread throughout your Results section.
Prepare the graphics for your Results section first. Remember that, in general, figures
are easier for viewers to read than tables. Add titles, labels, and captions to your figures to
focus your viewers’ attention on the important points.
Next, write the text that will accompany the graphics. Consider using a bulleted list
of short sentences. Remember to refer readers to appropriate graphics and to adhere to
conventions for the use of present and past tense.
The Poster Discussion Section
The Discussion section of a poster has two major purposes: (1) to interpret or
explain the results presented and (2) to summarize the most important fi ndings of
the work. These two purposes form the move structure for the Discussion section
(figure 9.4).
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1. Interpret or Explain Results
2. Conclude with a Take-Home Message
Figure 9.4 Visual representation of the move structure for a
typical poster Discussion section.
Move 1 (Interpret or Explain Results) is often integrated into the poster Results
section, thereby becoming a combined Results and Discussion (R&D) section.
An example of a combined R&D section is shown in figure 9.1. In such posters,
interpretative remarks (Discussion) are included right along with the graphics
(Results). In this way, space is conserved, and viewers can read and interpret
the data simultaneously (usually easier than looking back and forth between the
two sections). For instructional purposes, however, we have placed move 1 in
the Discussion section, and we use a stand-alone Discussion section in the three
hypothetical posters presented below. We follow this approach, in part, to maintain a clear distinction between results (just the facts) and discussion (interpretation of the facts).
The poster Discussion section ends with a take-home message (move 2). The
take-home message sums up the essential conclusions of the presented work (i.e.,
those points you most want your viewers to remember). Because of its importance,
move 2 is often given a separate heading (e.g., “Conclusions” or “Key Points”).
Most take-home messages are only a few sentences (or bulleted items) in length.
Some authors also include brief remarks about work in progress or future work at
the end of move 2. Move 2 is generally written for a broad audience and thereby
completes the bottom of the hourglass.
With these issues in mind, let’s examine the Discussion sections of our three
hypothetical posters. Each section is divided into two parts: Discussion and
Conclusions. Excerpt 9I uses a bulleted list to present the discussion points;
excerpts 9H and 9J use a paragraph format. Both styles are common and illustrate
that there is no one right way to present information. Excerpt 9J also includes
a scheme, which is common in posters that present a synthesis. In all three
excerpts, the Conclusions sections comprise one or two sentences and are written without bullets.
As you read through these Discussion sections, you will notice that they are
quite short. Moreover, the discussion points within these sections are often used
to highlight, explain, or reiterate key findings rather than to truly interpret data.
In addition, unlike a journal article, few references are made to the literature.
These common practices illustrate that the main emphasis in posters is to present, rather than interpret, results. This emphasis reflects both the newness of
the data presented (late-breaking results may not yet be fully understood) and
the interactive role of the poster (to promote an exchange of ideas and dialog).
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Nevertheless, a few interpretative remarks are encouraged; viewers want to know
what you think about your data.
Exercise 9.15
Consider the poster Discussion sections in excerpts 9H–9J as you answer the
following questions:
a. What writing features do you notice? Consider such features as the use of
fragments versus complete sentences and bulleted lists versus paragraphs.
b. How well do the excerpts adhere to the move structure in figure 9.4?
c. Which excerpts use concluding remarks to highlight work in progress?
Excerpt 9H (a poster Discussion section based on Llompart et al., 2001)
DISCUSSION
PCBs are more difficult to extract from full-fat milk than skim milk, suggesting that
PCBs are more strongly retained in the full-fat matrix. Even at 100 C, SPME without
saponification was not efficient. Saponification of milk fats to their corresponding
glycerols and carboxylates appears to facilitate the release of PCBs.
CONCLUSIONS
Saponification enables a more efficient SPME process for the detection of PCBs in full-fat
milk. An increase in response of 4 to 9 times can be achieved depending on the PCB
congener.
Excerpt 9I (a poster Discussion section based on Vesely et al., 2003)
DISCUSSION
During long-term storage (4–12 wk) at elevated temperatures (30 C), American-style
beers develop a stale fl avor. Nine aldehydes were analyzed as possible contributors to
this flavor loss:
■
5 Strecker aldehydes (Figs. 3 and 4). All 5 aldehydes increased during storage, but
none exceeded more than 4.3% of their respective flavor thresholds.
■
Pentanal and hexanal (degradation products of linoleic acid). Both aldehydes were
less than 1% of their flavor thresholds.
■
(E)-2-nonenal (a degradation product of linoleic acid). This aldehyde increased
to 27% of its flavor threshold but is not expected to contribute to stale beer flavor
(Schieberle & Komarek, ACS, Chicago, Fall 2001).
■
Furfural (a heat exposure indicator). This aldehyde increased more than 2-fold but
reached only 1% of its flavor threshold.
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CONCLUSIONS
The increase after 12 weeks for most aldehydes was significant (16-fold for furfural, 7-fold
for 2-methylpropanal); however, no aldehyde approached its respective flavor threshold.
We are currently exploring additive or synergistic effects among these aldehydes to
explain the stale fl avor of aged beer.
Between vs. Among
See appendix A for more information on these commonly confused words.
Excerpt 9J (a poster Discussion section based on Boesten et al., 2001)
DISCUSSION
A proposed mechanism is shown in Scheme 1. The re-facial attack of CN– to the intermediate imine 4 appears to be preferred, forming (R,S)-3. (R,S)-3 is less soluble and precipitates out of solution; (R,R)-3 is more soluble and epimerizes in solution via the imine 4.
Scheme 1
Ph
CONH2
N
H
re-face
attack
HCN
Ph
HN
(R)-4
HCN
CONH2
CN
H
preferential
crystallization
(R,S)-3
Ph
HN
CONH2
CN
H
(R,R)-3
CONCLUSIONS
(R)-Phenylglycine amide 1 is an excellent chiral auxiliary in the asymmetric Strecker
reaction of pivaldehyde 2. In water at 70 C, the (R,S)-3 product was isolated in 93%
yield and dr 99/1. Work is underway to convert (R,S)-3 to (S)-tert-leucine and thereby
complete the asymmetric Strecker reaction.
Exercise 9.16
Write a combined Results and Discussion section:
a. Either combine excerpts 9E (Results) and 9H (Discussion) or combine
excerpts 9F (Results) and 9I (Discussion). Approach the task by rewriting the
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information in 9H or 9I (stand-alone Discussion sections) so that they accompany the graphics in 9E or 9F (Results).
b. Which approach do you prefer: stand-alone Results and Discussion sections
or merged Results and Discussion sections? Why?
We conclude this part of the chapter by identifying some writing conventions
that are commonly used in the poster Discussion section:
■
Bulleted or numerical lists: Discussion items and conclusions may be
presented in paragraph or list form. In Discussion section lists, complete
sentences are more common than fragments. (See the guidelines presented
in the poster Methods section for formatting these lists.) Conclusions are
usually set apart from the Discussion section with a separate heading.
■
Citations: Citations may be included in a poster Discussion section. (See
the discussion of the poster Introduction section, below, for information
on citations and references.)
■
Hedging: Hedging words should be used to soften interpretive remarks in
posters. A few examples are presented below; hedging words are italicized:
Saponification of milk fats to their corresponding glycerols and carboxylates
appears to facilitate the release of PCBs from the sample matrix.
These results, however, do not rule out the possibility that additive or synergistic effects among these aldehydes may contribute to the stale flavor of
aged beer.
The latter process is attributed to the reversible reactions of the amino
nitriles.
■
Verb tense: Poster Discussion sections use both past tense (to summarize
findings observed in the past) and present tense (to state fi ndings and
conclusions that are expected to be true over time). Because the Discussion
section focuses on conclusions, present tense is used more often.
Past tense
With saponification, the SPME process was 4 to 9 times more
effective.
None reached more than 4.3% of their flavor threshold.
Present tense During long-term storage, American-style beers develop a stale
flavor.
PCBs are more difficult to extract from full-fat milk than
skim milk.
In methanol at room temperature, the re-face attack of CN– to
the intermediate imine 4 is preferred.
(R)-Phenylglycine amide 1 is an excellent chiral auxiliary in
the asymmetric Strecker reaction of pivaldehyde 2.
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325
■
Voice and we: Both active and passive voice may be used in the poster
Discussion section. The word we should be used sparingly (and is not used
in excerpts 9H–9J), but it can be used to signal a decision, interpretation, or
conclusion made by the authors.
Active voice Furfural increased more than 2-fold.
SPME (without saponification) is not an efficient technique.
We next plan to convert (R,S)-3 to (S)-tert-leucine.
Saponification enables a more efficient SPME process.
Passive voice Nine aldehydes were analyzed as possible contributors to this
flavor loss.
This aldehyde . . . is not believed to be a key contributor to
flavor loss.
The latter process is attributed to the reversible reactions of
amino nitriles.
Hedging
See appendix A.
Active and Passive Voice
See appendix A.
Exercise 9.17
Examine the use of past and present tense in excerpts 9H–9J. What conclusions
can you draw?
Exercise 9.18
Find instances of hedging in excerpts 9H–9J. Propose generalizations about
when hedging is appropriate and when it is not necessary in a poster Discussion
section.
9D Writing on Your Own: Draft Your Poster Discussion Section
Consider the key results of your work. How can you use text to highlight, explain, and
interpret these results? Decide if you want a combined Results and Discussion section, with
explanatory remarks included along with the graphics, or a stand-alone Discussion section.
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Think about the take-home message that you want your viewers to get from your
poster. How can you best summarize your work? Try to limit your take-home message to
one or two sentences.
The Poster Introduction Section
The poster Introduction is typically not written until you know the full and
final content of your poster. The first move of the Introduction focuses on the
importance of your research area (figure 9.5). It should be clear to your viewers,
after reading only the first few sentences of your Introduction, what your general research area is and why the area is important (submove 1.1). Background
information is shared largely for the purpose of establishing this importance and
should be kept to a minimum (submove 1.2). Importance is also commonly established by pointing out gaps in the field (i.e., work that has yet to be done or problems that need to be solved). In-text citations to essential works are often included
(although they are not required); an abbreviated citation format may be used to
conserve space (see the end of this part of the chapter for more information on
citations). If citations are not included, you should still know what major works
influenced your work, in case someone asks.
The second move of the poster Introduction previews the specific accomplishments of the work and is often given its own subheading (e.g., Research Objectives
or Goals). The focus should be on research goals that have been achieved and
are presented in the poster. Move 2 has a narrower focus than move 1; hence,
the poster Introduction follows the broad-to-narrow hourglass structure. As a
test to see if your Introduction addresses moves 1 and 2 sufficiently, ask yourself if a viewer, after reading only your Introduction, could answer the following
questions: (1) What research area is addressed? (2) Why is this area important?
(3) What specific accomplishments will the authors present in their poster?
1. Establish Importance of Research Area
1.1 Introduce the research area
1.2 Emphasize importance (through background information,
gap statements)
Cite essential
works
(optional)
2. Preview Accomplishments
(Identify major goals that have been achieved)
Figure 9.5 A visual representation of the move structure for a typical poster Introduction section.
Writing the Poster Text
327
With the organizational structure of the poster Introduction in mind, let’s
examine the Introduction sections of our three hypothetical posters. As you
glance through these excerpts, notice that the subheadings (e.g., Overview
and Importance and Research Objectives) direct the reader’s attention to
essential information in the most efficient manner. Also note that no bulleted lists are used in these Introductions. Although bulleted lists are common in other sections of the poster, they are less common in the Introduction.
Finally, we include a word count in each Introduction, to give you a better idea
of how long an Introduction should be. Most poster Introductions are under
150 words.
Conciseness
For the poster Introduction, a good rule of thumb is to stay under 150 words.
Exercise 9.19
Read excerpts 9K–9M. Based only on the information presented in these
Introduction sections, answer the three questions that viewers should be able to
answer after reading a poster Introduction:
a. What research area is addressed?
b. Why is this area important?
c. What specific accomplishments will the authors present in their poster?
Excerpt 9K (a poster Introduction based on Llompart et al., 2001)
INTRODUCTION
Overview and Importance. The pollutants known as polychlorinated biphenyls
(PCBs) are widely distributed in the environment due to their extensive use in the
past, lipophilic (fat-loving) character, and general chemical stability. Moreover,
PCBs tend to accumulate in the food chain. Thus, several countries have established
recommended maximum limits for PCBs in food products. Among these products,
milk is especially important because of its extensive and widespread consumption
by humans.
Objective. To date, there is no simple or rapid procedure for testing PCBs in milk.
Headspace solid-phase microextraction (HSSPME) is a promising approach, but
only a few works have applied this technique to milk (1, 2). Here, we present a
simple and rapid saponification-HSSPME procedure for extracting PCBs from milk.
(119 words)
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Excerpt 9L (a poster Introduction based on Vesely et al., 2003)
INTRODUCTION
Overview and Importance. American packaged beers lose their fl avor and become
stale during storage. Carbonyl compounds, particularly aldehydes, may be involved in
this process. Aldehydes are formed in beer through one of several possible mechanisms
including Strecker degradation of amino acids or linoleic acid (Pollock. In Brewing
Science, Acad. Press, 1981, 371). In most cases, their concentrations are very low. As
a result, it has been difficult for brewing chemists to monitor their levels in beer and
thereby deduce their role in affecting beer fl avor.
Goal. Using a newly optimized derivatization and solid-phase microextraction (SPME)
process, low-level aldehyde concentrations in beer stored for 4, 8, and 12 weeks at 30
C were monitored. Although all aldehydes increased in concentration, no aldehyde
exceeded its fl avor threshold. (126 words)
Excerpt 9M (a poster Introduction based on Boesten et al., 2001)
INTRODUCTION
The synthesis of -amino acids is important because they are used extensively in pharmaceuticals, agrochemicals, and as chiral ligands. The Strecker reaction is historically
one of the most versatile ways to synthesize -amino acids, but this method yields only
50% of a single enantiomer. Higher yields can be achieved by using chiral auxiliaries,
but auxiliaries are often high in cost and low in availability.
Overview. To solve these problems, we present the first example of a crystallizationinduced asymmetric transformation using optically pure (R)-phenylglycine amide 1 as
a chiral auxiliary. The (R,S)-3 diastereomer precipitates out of solution in 76–93% yield
with a diastereomeric ratio (dr) 99/1. (106 words)
Exercise 9.20
Glance again at excerpts 9K–9M. How well do the Introduction sections adhere
to the move structure in figure 9.5? What generalizations can you make about
sentence format, citation format, verb tense, and voice?
We conclude this part of the chapter by identifying some writing conventions
that are characteristic of poster Introduction sections:
■
Bulleted or numbered lists: Lists are uncommon in poster Introductions.
More often, the Introduction is written in paragraph form with the text
left-only or right-and-left justified (see chapter 10).
■
Citations: In-text citations (typically fewer than four) are often included
in posters, most commonly in the Introduction. Either a numerical or
Writing the Poster Text
329
author–date format may be used. Numerical formats are often preferred
because they conserve space. When citations are used, a References section
must also be included (see below). In some instances, authors insert the reference information (not merely a citation) into the text (e.g., “(Boesten et al.
Org. Lett. 2001, 3, 1121)”). In this case, a References section is not needed.
■
Verb tense: The poster Introduction is written primarily in the present tense,
though instances of the present perfect (to signal that knowledge gained from
work completed in the past is still believed to be true in the present) are also
possible.
Present
In most cases, their concentrations are very low.
We present the first example of a crystallization-induced
asymmetric synthesis.
Present perfect Thus, countries have established recommended maximum
limits for PCBs . . .
As a result, it has been difficult for brewing chemists to
monitor their levels . . .
■
Voice and we: Both active and passive voice are used in the poster Introduction,
although active voice is more common. The word we can be used to signal the
current work, that is, the work that the authors will present in the poster.
Passive voice Low-level aldehyde concentrations were monitored.
Active voice We present an asymmetric Strecker reaction where . . .
Citations and References
Posters generally include a few citations and a References section. (See chapter 17.)
Present Perfect
See table 6.2.
Exercise 9.21
Rewrite the following passages (adapted from Webber et al., 2004, and Wei et al.,
2001, respectively) so that they are more suitable for a poster Introduction section. Look for problems with lists, citations, verb tenses, voice, and conciseness.
a. This poster is about asbestos fibers that are naturally occurring hydrated
silicate mineral fibers that found myriad uses in the twentieth century.
However, airborne asbestos fibers became the well-recognized cause of
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asbestosis, bronchogenic carcinoma, and mesothelioma during the latter
half of that century (Hansen et al., 1998; Timbrell, 1982). In this poster, we
demonstrate the following:
■
■
■
■
how we reconstructed airborne asbestos concentrations from the last century through a combination of
paleolimnological methods
particle-separation techniques
analytical transmission electron microscopy
b. As everyone knows, plants have been used for centuries in herbalism, homeopathy, and aromatherapy because of their medicinal qualities. The long-term
use of plants has led to recent observations about their antioxidant properties
(1, 2). Many scientists have observed antioxidant activities in compounds
derived from the volatile constituents (3, 4) and essential oil extracts5,6 of
plants. They have reported that ingestion of these volatile chemicals can
prevent lipid peroxidation, which is associated with diseases such as cancer,
leukemia, and arthritis. In the present study, analysis and antioxidative tests
on the volatile extract isolated from a commercial beer were performed. Why
did we choose beer? We chose beer because
1. it is one of the most popular beverages in the world
2. its popularity as a beverage is second only to soft drinks
9E Writing on Your Own: Draft Your Poster Introduction Section
Consider the importance of your research area, more generally, and your own research,
more specifically. What background information will your audience need to grasp the
importance of this project? Identify a few key references that you could include in your
Introduction. List the key objectives of your research that are addressed in the poster.
Then write the Introduction to your poster.
Considering Additional Poster Sections
We conclude the chapter with a brief examination of two additional poster
sections: Acknowledgments and References.
The Poster Acknowledgments Section
Funding agencies and any individuals who helped you in the work and who are
not named as authors of your poster should be acknowledged. If space permits,
consider including a funding agency logo. (See figure 9.1 for an example of a
poster Acknowledgments section with a logo.)
Writing the Poster Text
331
The Poster References Section
A References section is needed if you cite others’ works in your poster, unless you
inserted an abbreviated reference directly into the text. If you include citations
in only one section of your poster (e.g., the Introduction), the References section
can be placed at the end of that section; otherwise, include the references at the
end or bottom of your poster. Format the references with the citation format used
in the poster: number them in citation order (if you used numerical citations) or
arrange them alphabetically (if you used author–date citations). Because of space
limitations, references may be abbreviated. Consider the following examples for a
poster with numerical citations:
REFERENCES
1. Smedes & Boer. Trends Anal. Chem. 1997, 16, 503.
2. Vesely et al. J. Agric. Food Chem. 2003, 51, 6941.
3. Erickson. In Anal. Chem. of PCBs, Lewis Publ. 1997.
Exercise 9.22
Rewrite these references using an abbreviated format:
a. Fredriksson, S.-Å.; Hulst, A. G.; Artursson, E.; de Jong, A. L.; Nilsson, C.;
van Baar, B. L. M. Forensic Identification of Neat Ricin and of Ricin from
Crude Castor Bean Extracts by Mass Spectrometry. Anal. Chem. 2005, 77,
1545–1555.
b. Hansen, N.; Klippenstein, S. J.; Miller, J. A.; Wang, J.; Cool, T. A.; Law, M. E.;
Westmoreland, P. R.; Kasper, T.; Kohse-Hoinghaus, K. Identification of C5H x
Isomers in Fuel-Rich Flames by Photoionization Mass Spectrometry and
Electronic Structure Calculations. Phys. Chem. A 2006, 110, 4376–4388.
c. Heimann, A. C.; Jakobsen, R. Experimental Evidence for a Lack of
Thermodynamic Control on Hydrogen Concentrations during Anaerobic
Degradation of Chlorinated Ethenes. Environ. Sci. Technol. 2006, 40, 3501–3507.
d. Lockshin, R. A., Tilly, J. L., Zakeri, Z., Eds. When Cells Die: A Comprehensive
Evaluation of Apoptosis and Programmed Cell Death; Wiley-Interscience:
New York, 1998.
9F Writing on Your Own: Add Your Poster Title, Author List, Acknowledgments, and References
Add the title and author list to your poster (see chapter 8). If needed, write References and
Acknowledgments sections following recommended formats. Proceed to chapter 10 to
work on the layout of your poster.
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Chapter Review
Check your understanding of what you’ve learned from this chapter by defining
each of the following terms, in the context of the chapter, for a friend or colleague
new to the field:
conference proceedings
poster sessions
dangling graphics
sentence fragments
parallelism
As a review, explain the answers to the following questions to a friend or colleague who has not yet written text for a scientific poster:
■
What is the purpose of a poster?
■
Who is the audience of a poster?
■
What is the broad organizational structure of a poster?
■
What are the moves of each section of a poster?
■
What are common conventions regarding abbreviations, capitalization, and
parentheses in a poster?
■
In what sections of a poster are incomplete sentences appropriate? When
should they not be used? In what sections are bulleted lists appropriate?
■
How and where should hedging be used in a poster?
■
In which section are citations most common? What is the average number of
citations in a poster? Where are references listed?
Additional Exercises
Exercise 9.23
Sentences a–c are taken from journal articles. For each, (1) indicate which
poster section the information would belong in (Introduction, Methods, Results,
Discussion) and (2) rewrite the information so that it is appropriate for a poster.
a. Filters containing PM2.5 collected at the five sites were extracted with PBS to
give a solution/suspension of PM2.5. (From Dellinger et al., 2001)
b. The isotherms for RAMEB-enhanced minerals show lower adsorption as
compared to the pure minerals for all but KA 9% RAMEB samples. (From
Jozefaciuk et al., 2001)
c. Our results suggest that Cr3 has an impact on DNA, DNA topology, and
consequently processes leading to cell growth and proliferation. This could
Writing the Poster Text
333
ultimately lead to the mutagenic and carcinogenic potential of Cr3 . Because it
is known that humans exposed to different Cr3 species accumulate high levels
of Cr3 intracellularly (17), presented results may have an impact on human
intake of Cr3 as a nutrition additive. (Adapted from Plaper et al., 2002)
Exercise 9.24
Reflect on what you have learned about writing text for a poster. Select one of the
reflection tasks below and write a thoughtful and thorough response:
a. Posters must be written and formatted to communicate important ideas with
a minimal amount of effort on the part of viewers.
■
■
■
What are the keys to an effective poster?
In what ways do bulleted and numbered lists help?
How does the inclusion of graphics assist viewers?
b. Reflect on the challenges associated with deciding what to include in and
what to exclude from a poster.
■
■
■
■
What types of information seem to be obligatory for inclusion?
What types of information seem to be optional?
What types of information should be avoided?
What questions will you pose to yourself to guide you in making these
decisions?
c. Reflect on the differences between a poster and a journal article.
■
■
■
334
In what ways are posters and journal articles similar?
In what ways are posters and journal articles different?
What particular features contribute to poster effectiveness?
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10
Designing the Poster
The visual appeal of a poster is important, but clever graphics
and design are no substitute for good science.
—Frances Blanco-Yu, Seton Hill University
The purpose of this chapter is to help you design a poster that is visually appealing.
Specific attention is paid to poster layout, font, and color. These design elements
are illustrated with posters that we have created using the text introduced in
chapter 9. Of course, what makes a poster attractive is (at least in part) a matter
of taste, and many new design features will likely gain (and lose) popularity in
the next decade. We cannot anticipate these changes; hence, we focus on a few
basic principles of poster design that are likely to hold true over time. The guiding
principle is to present your science in a way that is clear, crisp, and uncluttered.
By the end of this chapter, you will be able to do the following:
■
Select the most appropriate layout for your poster
■
Select the font and font attributes for your poster
■
Select the color scheme for your poster
The Designing on Your Own activities throughout the chapter will guide you in
preparing your poster as you do the following:
10A Select a poster layout
10B Choose a font and font size
10C Add color and artwork
10D Finalize your poster
Although the focus of this chapter is on visual appeal, a good-looking poster is not
a substitute for good science. Viewers visit your poster to learn about your science,
not the latest trends in graphic design. Therefore, conservative, but effective, use
of design elements is preferred over flashy, distracting design. Commonly used
graphic design elements, such as photos, backgrounds, shadowing of text, and
“artsy” fonts can dramatically enhance the appeal and clarity of a poster, but if
used carelessly, they can turn the poster into a scattered and confusing mess.
The goal is to use your sense of aesthetics for color and your creative energies
to communicate your science and to make the poster inviting, accessible, and
memorable for your audience.
Not long ago, a “poster” consisted of 8–12 sheets of paper cut and pasted
onto individual pieces of colored construction paper. Today, most institutions
have plotters, which can print multicolored single-page posters (e.g., 3 ft 5 ft
or 0.91 m 1.52 m) from software files (e.g., Microsoft PowerPoint or Adobe
Illustrator). We assume that you have access to such plotters and software, and we
present only single-page posters in this textbook. Such advances make it possible
for even the first-time presenter to create professional quality posters.
Reading and Analyzing Writing
We begin by asking you to read guidelines (excerpt 10A) for authors presenting
a poster at an American Chemistry Society (ACS) conference. Most conferences
offer a similar set of guidelines to poster session authors. Much of the advice will
be the same, though some details will vary conference to conference (e.g., the
permissible dimensions of the poster). Hence, we strongly encourage you to check
the guidelines for your own specific conference.
Exercise 10.1
As you read excerpt 10A, look at the poster in figure 9.1. If possible, view the color
version on the Write Like a Chemist Web site. Comment on how well the poster
adheres to ACS guidelines.
Excerpt 10A (adapted from Instructions, Regulations for Speakers, Authors. American
Chemical Society Web site. http://portal.acs.org/portal/Navigate?nodeid=907
(accessed January 3, 2008))
Instructions for Poster Session Authors
ACS Policies for Poster Sessions
336
■
Each horizontal poster board measures 4 ft high 6 ft wide (including frame). All
presentations must be confined to the poster board itself.
■
Each author is responsible for mounting his/her material prior to the opening of the
poster session and for removing it IMMEDIATELY after the close of the session.
The Scientific Poster
■
Authors must remain with their posters for the duration of the session or as long as they
are scheduled by their division, as indicated in the technical program. You are expected
to display and discuss your results and answer questions from other attendees.
Design Suggestions for Scientific Posters
■
Allow ample time to prepare your poster. All poster materials (illustrations, charts,
and text) must be prepared in advance.
■
All posters should feature a title, your name, the name of the institution(s) where the
research was performed, and should credit other contributors, as appropriate.
■
Use a crisp, clean design. All lettering should be legible from about 5 ft (1.5 m) away.
Title lettering should be about 2 to 3 in. (5 to 7.5 cm). Subheading lettering should be
1/2 to 1 in. high (1.25 to 2.5 cm). Text lettering should be approximately 24 points
(1/4 in. or 0.625 cm).
■
Make illustrations simple and bold, with captions at least 3/8 in. high. Enlarge photos, tables, and charts to show pertinent details clearly.
■
Do not tell the entire research history. Present only enough data to support your
conclusions and show the originality of the work. The best posters display a succinct
statement of major conclusions at the beginning, followed by supporting text and a
brief summary at the end.
■
Displayed materials should be self-explanatory, freeing you for discussion.
■
Enhance your effectiveness by using a solid, colored background.
■
Utilize other techniques to improve the graphic impact. Use color to add emphasis
and clarity. Simplicity, ease of reading, etc. are more important than artistic flair.
Keep in mind that lighting may be dim inside large poster sessions, so make sure
your contrast and color combinations are easy to read.
■
You may want to bring handouts of your abstract or copies of your data, poster, or
conclusions to share with interested viewers.
Analyzing Poster Size and Layout
When well designed, posters are not simply journal papers pasted
onto boards. Nor are they mounted sets of PowerPoint slides. Rather,
posters . . . are a medium distinct in typography, layout, and style.
—Alley (2003)
When confronted with a single, very large “page” that comprises a poster, it is
sometimes difficult to know where to begin. The first step is to determine the
size of your poster because most conferences restrict poster size. The dimensions
are limited by the physical size of the poster board available; hence, conference
specifications must be followed. Unless stated otherwise, it is best to assume
Designing the Poster
337
that the poster board includes a frame, so your poster must be smaller than the
specifications given (e.g., for an ACS conference, the poster must be smaller than
4 ft 6 ft). Remember, too, that your final poster will have margins; the dimensions of these margins will be determined by the size of the plotter paper. Hence,
unless you want to trim the margins (this requires a poster cutter), you will need
to adjust for this space. Common poster dimensions (without margins) are 3 4,
3 5, or 4 6 (height length in feet) or 0.91 1.22, 0.91 1.52, or 1.22 1.83 (height length in meters).
After the poster size is selected, you are ready to lay out the poster. (We mean
this in a virtual sense, the layout on the “page” that you have created in your
poster-making software program.) A well-designed layout makes the poster flow,
that is, where the poster starts, how it moves (turns), and where it ends should
be clear to the reader. Viewers read from left to right and from top to bottom;
thus, the upper left corner is the “start” and the lower right corner is the “end.”
Guiding the reader through the “turns” is a bit more challenging. Two basic layout
schemes are presented (with their respective turning schemes): the column layout
and the row layout. Both are described in more detail below.
Flow
Flow refers both to the writing in a poster and to a poster’s layout.
“Good flow” transitions the viewer logically and smoothly from one idea or section to
the next.
Whichever layout you choose, be sure to include explicit headings in your
poster. Headings serve as navigational signposts for the reader. Because viewers
will spend only a few minutes at each poster, they need headings to guide them
through the poster and help them locate the information that they seek. Most
poster headings follow IMRD sequencing; for example, viewers expect introductory information (indicated by such headings as Introduction, Background, or
Objectives) to precede Methods. Furthermore, they expect Methods to precede
Results, and Results to precede the Discussion and Conclusions. In chapter 9,
we noted that a variety of terms can be used for section headings; for example,
Overview and Importance may be substituted for Introduction or used as a subheading within the Introduction section. There are no fi xed conventions about the
exact words to be used in headings and subheadings; what is anticipated, however,
is that the introductory information comes first and the conclusions come last.
Poster Headings
Explicit headings serve as navigational signposts; clear headings contribute to the flow of
an effective poster.
338
The Scientific Poster
Poster Title Extends Across the Top (centered or left-justified)
Linus Pauling, Albert Einstein, and Francis Crick (use first and last names if space permits)
Department of Chemistry, University of New Mexico, Albuquerque, NM
Introduction
Methods
Results (cont.)
Discussion
Results
Conclusions
Research Objective
References
Acknowledgments
Figure 10.1 A typical column (or newspaper) layout for a scientific poster.
The column layout, illustrated in figure 10.1, is modeled after a newspaper;
thus, it should be familiar to most readers. The column format is used by the vast
majority of authors. Columns make it easier for multiple viewers, standing side
by side, to read your poster at once. The title, authors, and affiliations go across
the top of the poster and can be left-justified (as shown in figure 10.1) or centered.
The sections of the poster begin in the upper-left corner. The viewer reads one
column, reaches the bottom, and moves over to the top of the next column (to the
right). The text itself moves the reader’s attention down the column, making the
flow easy to follow. The number of columns varies with the size of the poster, but
three or four columns are typical.
We illustrate the column layout in an actual poster in figure 10.2. The poster
(using the written text, tables, and figures from chapter 9) includes three columns. In this case, the three columns are approximately equal in width, but
unequal column widths are also allowed (and common). Vertical lines may be
used to separate the columns, although we did not do this in figure 10.2. Note,
too, that Table 1 is not split between two columns; you must never start a table
(or figure) at the bottom of one column and then continue it in the next. Another
example of a three-column layout is illustrated in figure 9.1, where numbered
subheadings (1, 2, 3, 4) are used to guide readers through a combined Results
and Discussion section.
The row layout is illustrated in figure 10.3. This design inevitably includes
two rows; typically, there is not enough space for more than two. The advantage
Designing the Poster
339
PCBs in Milk Samples by Saponification Solid-Phase Microextraction
María Llompart, Manuel Pazos, Pedro Landín, and Rafael Cela
Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Santiago de Compostela, Spain
INTRODUCTION
RESULTS (CONT.)
METHODS (CONT.)
Overview and Importance. The pollutants known as polychlorinated
Saponification and HSSPME Procedures
biphenyls (PCBs) are widely distributed in the environment due to their extensive
use in the past, lipophilic (fat-loving) character, and general chemical stability.
Moreover, PCBs tend to accumulate in the food chain. Thus, several countries
have established recommended maximum limits for PCBs in food products.
Among these products, milk is especially important because of its extensive and
widespread consumption by humans.
• PCB-spiked milk samples were placed in headspace vials. When saponification
was performed, samples were treated with NaOH, sealed, immersed in water
(100 °C), and equilibrated for 6 min.
(3) After Saponification. Skim milk response increased 5 to 10 times; full-fat milk
response increased 4 to 8 times, depending on PCB congener (Fig. 2).
• During HSSPME, the fiber was exposed to the headspace over the sample for 5240 min as the sample was stirred.
Sample Analysis
Objective. To date, there is no simple and rapid procedure for testing PCBs in
milk. Headspace solid-phase microextraction (HSSPME) is a promising approach,
but only a few have applied this technique to milk (1, 2). Here, we present a
simple and rapid saponification-HSSPME procedure for extracting PCBs from
milk.
References
1. DeBruin et al. J. Anal Chem. 1998, 70, 1986-1992.
2. Röhring & Meische. J. Anal. Chem. 2000, 366, 106-111.
• PDMS-fibers were analyzed by GC -electron capture detection using a HP 5890
series II GC. PDMS-DVB fibers were analyzed by GC/MS-MS using a Varian
3800 GC with ion trap (Varian Saturn 2000).
RESULTS
(4) Procedure Validation. Calibration results were linear (R2 > 0.994) and
reproducible (RSD < 11.0 %) over a wide range of concentrations. Good
results were also achieved with a certified milk sample (Table 2).
(1) Before saponification. High sensitivity to PCBs in skim milk (Fig. 1A) but not
full-fat milk (Fig. 1B) was achieved.
Table 2. Procedure validation with certified milk (25% fat).
METHODS
Fig. 1 (A)
PCBs in skim milk.
Reagents and Materials
• Full-fat (3.61%) and skim milk (0.34%) samples were obtained from local
supermarkets and spiked with one of eight PCB congeners (1-100 ng/mL).
Fig. 1 (B)
PCBs in full-fat milk.
PCB-28
PCB-52
PCB-101
PCB-105
PCB-118
PCB-138
PCB-153
PCB-180
(2) Saponification Trials. Factors varied to improve extraction (Table 1).
• Spiked samples were homogenized, held at 4 °C for 24 h, frozen, then thawed 1 h
before analysis.
• SPME holders with one of two fiber assemblies were used:
100 m PDMS (poly(dimethylsiloxane))
65 m PDMS-DVB (poly(dimethylsiloxane)divinylbenzene)
Fig. 2. PCBs in full-fat milk with saponification.
PCB
PCB-52
PCB-118
PCB-153
PCB-156
PCB-180
certified value
(ng/g)
1.16 ± 0.17
3.19 ± 0.24
18.6 ± 1.1
1.64 ± 0.11
9.29 ± 0.26
recovery
(%)
75
97
98
102
88
DISCUSSION
PCBs are more difficult to extract from full-fat milk than skim milk, suggesting that
PCBs are more strongly retained in the full-fat matrix. Even at 100 °C, SPME without
saponification was not efficient. Saponification of milk fats to their corresponding
glycerols and carboxylates appears to facilitate the release of PCBs.
Table 1. Factors varied in optimization process.
Factor
Values tried
Optimized value
1. NaOH vol (mL)
0.5, 2.0, 3.5
2.0-3.5
2. NaOH conc. (%) 20, 30
20%
3. Time (min)
30, 60
60*
4. Fiber
PDMS, PDMS-DVB
PDMS-DVB
5. Stirring
yes, no
yes
*longer times were better but too slow for desired approach
Figure 10.2 The column layout, illustrated in a poster based on Llompart et al. (2001).
CONCLUSIONS
Saponification enables a more efficient SPME process for the detection of PCBs
in full-fat milk. An increase in response of 4 to 9 times can be achieved depending
on the PCB congener.
Acknowledgment. We gratefully acknowledge financial support from the Xunta de
Galicia (Conselleria de Medio Ambiente), project PGIDT99MA23701.
Poster Title Extends Across the Top (centered or left-justified)
L. Pauling, A. Einstein, and F. Crick (use first and last names unless space is tight)
Department of Chemistry, University of New Mexico, Albuquerque, NM
Introduction
Methods
Results
Discussion
References. (1) Sanders et al. JACS 2003, 78, 89. (2) Adamson et al. Org. Lett. 2004,
10, 57. Funding. NSF (CHM 3000987)
Figure 10.3 A typical row layout for a scientific poster. Pure row layouts are uncommon in posters.
of this approach is that it allows two or more figures to be arranged side by side
for easy comparison. However, this layout is difficult to follow visually, and it
requires viewers to move from left to right twice (for two rows) as they read
the poster, which is an inconvenience if the conference is crowded. For these
reasons, most authors avoid the pure row layout and instead used a combined
column-and-row approach, illustrated in figure 10.4. The left-hand column reads
from top to bottom (column layout), but the Results section (with two sets of
figures placed side by side) and the Discussion and Conclusions sections are in
row layout.
Figures 10.1–10.4 represent just a few examples of how to lay out a poster. Each
poster is different; hence, each will require variations on these themes. The only
hard-and- fast rule is that the flow should be logical and clear to your viewers.
Our discussion thus far might suggest that one writes the text of the poster
first and then simply “cuts and pastes” it into the appropriate layout. In fact, the
text evolves in an iterative way. One drafts the text first, capturing the key ideas
that will be shared, but then the text is altered (numerous times) until it fits into
the allotted space. Typically, you have less space than you first imagined, requiring that you reduce the number of lines and words in the text. The final texts
presented in chapter 9 went through just such an iterative process. We wrote the
text first, realized (all too often) that the text would not fit, and then revised it to
make it more concise.
Designing the Poster
341
Detection of Low-Level Aldehydes in Aged Beer
Petr Vesely†,‡, Lance Lusk,† Gabriela Basarova,‡ John Seabrooks,† and David Ryder†
Miller Brewing Company† and Institute of Chemical Technology,‡ Prague, Czech Republic
Introduction
Results
Spiked Beer Samples
Aged Beer Samples
A beer sample was spiked with 9 aldehydes and
derivatized. The chromatogram is shown in Fig. 1.
Aldehydes were detected by m/z 181 (Fig. 2).
All aldehydes increased during storage (Fig. 3), but none
exceeded their flavor threshold (Fig. 4).
1600
1400
4 weeks
heat exposure
8 weeks
1200
Percent increase
(relative to control)
Overview and Importance
American packaged beers lose their flavor and become stale during
storage. Carbonyl compounds, particularly aldehydes, may be
involved in this process. Aldehydes are formed in beer through one
of several possible mechanisms including Strecker degradation of
amino acids or linoleic acid (Pollock. In Brewing Science, Acad. Press,
1981, 371). In most cases, their concentrations are very low. As a
result, it has been difficult for brewing chemists to monitor their
levels in beer and thereby deduce their role in affecting beer flavor.
12 weeks
1000
800
600
degradation of amino acids
degradation of linoleic acid
400
200
.
Fig. 1. Chromatogram of 9 aldehydes in spiked beer. Concentrations were
determined by adding together both isomers (e.g., 1, 1’).
Percent flavor threshold
Acknowledgment. The authors gratefully acknowledge
support from the Miller Brewing Co.
fu
rfu
ra
l
he
xa
na
l
(E
)-2
-n
on
en
al
30%
Samples. The beer samples (American lagers) were stored at 30 ˚C
for 4, 8, or 12 wk. The controls were stored at 0 ˚C for 12 wk.
On-Fiber Derivatization and Detection of Aldehydes
• The derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBOA) was absorbed onto a 65-_m
PDMS/DVB SPME fiber (10 min, 50 ˚C).
• The fiber was placed in the sample headspace (50 ˚C, 60 min).
• The beer aldehydes selectively reacted with the PFBOA in
the fiber.
• The oximes that formed were desorbed and detected by GC/MS
(DB-5 30 m _ 0.25 mm _ 0.50 _m; He carrier gas at 1.1 mL/min;
splitless, injector 250 ˚C).
pe
nta
na
l
Derivatized aldehyde
Fig. 3. Increase of aldehydes (grouped by source) during storage.
Methods
20%
10%
degradation of amino acids
degradation of linoleic acids
heat exposure
l
ra
na
ph
en
yla
(E
)-
2-
no
rfu
ne
xa
he
fu
na
l
l
l
e
na
yd
nta
eh
ld
ta
pe
l
na
io
eth
ce
l
na
uta
ylb
ylb
eth
eth
m
m
3-
2-
m
l
na
uta
na
pa
ro
ylp
eth
m
l
0%
2-
Methods Validation
• Calibration curves were prepared for 9 aldehydes
(linearity >0.96).
• Each beer sample was measured 10 times (variance <5.5%).
• Recovery was determined by spiking beer samples with 10 ppb of
the standard aldehyde (recoveries 89-110%).
m
eth
io
na
ph
l
en
yla
ce
ta
ld
eh
yd
e
eth
ylp
ro
pa
na
l
2-m
eth
ylb
uta
na
l
3-m
eth
ylb
uta
na
l
0
2-m
Goal. Using a newly optimized derivatization and solid-phase
microextraction (SPME) process, low-level aldehyde concentrations
in beer stored for 4, 8, and 12 weeks at 30 °C were monitored.
Although all aldehydes increased in concentration, no aldehyde
exceeded its flavor threshold.
Derivatized aldehyde
Fig. 2. Aldehydes were identified by m/z 181 (methional is shown).
Fig. 4. Percent of flavor threshold at 12 weeks for 9 aldehydes.
Discussion
During long-term storage (4–12 wk) at elevated temperatures (30 ˚C), American-style beers develop
a stale flavor. Nine aldehydes were analyzed as possible contributors to this flavor loss:
• 5 Strecker aldehydes (Figs. 3 and 4). All 5 increased during storage, but none exceeded >4.3% of
their respective flavor threshold.
• Pentanal and hexanal (degradation products of linoleic acid). Both aldehydes were <1% of their
flavor thresholds.
• (E)-2-nonenal (a degradation product of linoleic acid). This aldehyde increased to 27% of its flavor
threshold but is not expected to contribute to stale beer flavor (Schieberle & Komarek, ACS,
Chicago, Fall 2001).
• Furfural (a heat exposure indicator). This aldehyde increased more than 2-fold but reached only 1%
of its flavor threshold.
Conclusions
The increase after 12 wks for most aldehydes
was significant (16-fold for furfural, 7-fold for 2methylpropanal); however, no aldehyde
approached its respective flavor threshold.
We are currently exploring additive or
synergistic effects among these aldehydes to
explain the stale flavor of aged beer.
Figure 10.4 A poster based on Vesely et al. (2003), which illustrates a combined column-and-row layout. This approach allows figures to be placed side by side and
viewed from left to right.
Exercise 10.2
Below are early drafts of the text written for two posters introduced in chapter 9.
The drafts were ultimately shortened because of space limitations in the fi nal
posters. Without referring to the final posters, rewrite each text so that it is more
concise; aim for the final word/line counts noted for each draft.
a. Here is the initial draft of the Discussion section for the poster based on
Llompart et al. (2001). This draft is 83 words. The final version is 50 words
(with no bullets).
■
■
PCBs are more difficult to extract from full-fat milk than skim milk,
suggesting that PCBs are more strongly retained in the full-fat sample
matrix. Even at 100 C, SPME (without saponification) is not an efficient
technique.
Saponification of milk fats to their corresponding glycerols and carboxylates appears to facilitate the release of PCBs from the sample matrix. With
saponification, the SPME process was 4 to 9 times more effective, depending on the fat content of the milk and the PCB congener.
b. Here is the initial draft of the first paragraph in the Introduction section for
the poster based on Boesten et al. (2001). This draft is 98 words, and the final
version is 64 words.
The asymmetric synthesis of -amino acids is an important topic due
to their extensive use in pharmaceuticals and agrochemicals and as
chiral ligands. The Strecker reaction is historically one of the most
versatile ways to produce -amino acids, but this method has a
maximum yield of only 50% for a single enantiomer. Higher yields
can be achieved by using chiral auxiliaries, but auxiliaries have other
drawbacks, such as high cost, low availability, the need for purification,
and high loss rates. A possible solution to these problems would be
to use a chiral auxiliary in a crystallization-induced asymmetric
transformation.
10A Designing on Your Own: Select a Poster Layout
Look over the text that you have written for your poster (chapter 9). Next, decide what
section headings you will use, what graphics you will include in each section, and how
much space each section will require. When these pieces are in place, experiment
with layout and select a format (i.e., the column, row, or column-and-row format)
that is best for your poster. Begin revising your text and graphics so that they fit
the allotted spaces.
Designing the Poster
343
Analyzing Fonts and Font Size
Fonts can enhance or detract from an effective poster. There are two categories
of fonts: serif and sans-serif. Serif fonts have letters with little “tags” at the end
of each straight line. The lines in sans-serif fonts end abruptly without tags. Serif
fonts are considered more traditional, while sans-serif fonts have a more modern
look. The two most commonly used fonts among chemists are Times New Roman
(a serif font) and Arial (a sans-serif font). These and other fonts are illustrated in
table 10.1.
Serif and Sans-Serif Fonts
Serif font: A font with short, light lines or curves (called “serifs”) that project from the top or
bottom of a main stroke of a letter.
Sans-serif font: A clean modern font that has letters without serifs.
Many authors combine two different fonts in a poster. One approach is to
use a sans-serif font for the title and headings (e.g., Arial, Arial Black, Franklin
Gothic Heavy, or Tahoma) and a highly legible serif font for the text (e.g., Times
New Roman or Bookman Old Style). Arial is also a popular font for the poster
text. Three different two-font combinations are illustrated in figure 10.5. We
caution against using more than two fonts in your poster, or choosing overly
decorative or fancy fonts (there are hundreds to choose from). Select a crisp,
clean combination that is easy to read, and then continue with the rest of your
poster design.
Table 10.1 Some common serif and sans-serif fonts (all shown in 12 point size).
Font type
Serif
Sans-Serif
344
Font example
This is an example of Century.
This is an example of Book Antiqua.
This is an example of Bookman Old Style.
This is an example of Times New Roman.
This is an example of Arial.
This is an example of Century Gothic.
This is an example of Comic Sans MS.
This is an example of Franklin Gothic Medium.
This is an example of Tahoma.
The Scientific Poster
Introduction
Introduction
Introduction
The synthesis of ∝-amino acids is
important because they are used
extensively in pharmaceuticals,
agrochemicals, and as chiral ligands.
The Strecker reaction is historically
one of the most versatile ways to
synthesize ∝-amino acids, but this
method yields only 50% of a single
enantiomer. Higher yields can be
achieved by using chiral auxiliaries,
but auxiliaries are often high in cost
and low in availability.
The synthesis of ∝-amino acids is
important because they are used
extensively in pharmaceuticals,
agrochemicals, and as chiral ligands. The
Strecker reaction is historically one of the
most versatile ways to synthesize ∝amino acids, but this method yields only
50% of a single enantiomer. Higher yields
can be achieved by using chiral
auxiliaries, but auxiliaries are often high
in cost and low in availability.
The synthesis of ∝-amino acids is
important because they are used
extensively in pharmaceuticals,
agrochemicals, and as chiral
ligands. The Strecker reaction is
historically one of the most
versatile ways to synthesize ∝amino acids, but this method
yields only 50% of a single
enantiomer. Higher yields can be
achieved by using chiral
auxiliaries, but auxiliaries are
often high in cost and low in
availability.
Overview. To solve these problems,
we present the first example of a
crystallization-induced asymmetric
transformation using optically pure
(R)-phenylglycine amide 1 as a chiral
auxiliary. The (R,S)-3 diastereomer
precipitates out of solution in 76–93%
yield with a diastereomeric ratio (dr) >
99/1.
Heading font: Century Gothic
Text font: Arial
Overview. To solve these problems, we
present the first example of a
crystallization-induced asymmetric
transformation using optically pure (R)phenylglycine amide 1 as a chiral
auxiliary. The (R,S)-3 diastereomer
precipitates out of solution in 76–93%
yield with a diastereomeric ratio (dr) >
99/1.
Heading font: Comic Sans MS
Text font: Times New Roman
Overview. To solve these
problems, we present the first
example of a crystallizationinduced asymmetric
transformation using optically
pure (R)-phenylglycine amide 1 as
a chiral auxiliary. The (R,S )-3
diastereomer precipitates out of
solution in 76–93% yield with a
diastereomeric ratio (dr) > 99/1.
Heading font: Tahoma
Text font: Bookman Old Style
Figure 10.5 Three examples of two-font combinations; one font is used for the word “Introduction” (bolded), and a different font is used
for the text and heading. All font sizes are 9 points.
In addition to font style, authors must also pay careful attention to font size.
The rule of thumb recommended by the ACS (excerpt 10A) is that the text should
be easy to read from a distance of at least 5 feet (1.5 m). One way to check this on
your computer screen is to set your poster to 100% scale and literally step back
5 feet. This is often difficult, however, because the text is so large that only a small
portion of the poster can be viewed at any one time on the screen. Alternatively,
you can refer to table 10.2, which gives a range of font sizes that are common in
different sections of a poster using Arial font. You will need to adjust the font size
accordingly if you use a font larger or smaller than Arial. Most agree that font
sizes less than 24 points (1/4 in.) are too small and should not be used.
A poster should be easily read from a distance of 5 feet (1.5 m). Your smallest font size
should be at least 24 points (1/4 in.). (Point, abbreviated as pt., refers to font size.)
Text style and special effects (e.g., bold, italics, shadows) must also be considered when making decisions about fonts. Bolding can be used effectively, primarily for the title, authors’ names and affiliations, section headings, and graphics
labels (e.g., Table 1, Fig. 3) contained in titles or captions (not in the main text).
Too much bolding, however, can distract the viewer (or, worse, divert the viewer’s attention from important content) and make your poster difficult to read.
Table 10.2 Common font sizes for different sections of a poster in Arial font.
Poster Section
Height (in.)
Point size
(Arial)
Example (points in Arial font)
Titles
3
288
2
192
1
96
96
Headings, subheadings,
names, affiliations
1
96
1/2
48
Text, captions,
references
1/2
48
3/8
36
1/4
24
346
48
36
24
The Scientific Poster
Right and
left
justificatio
n
can
cause odd
spacing
between
words.
Right
and
left
justification
can cause
odd spacing
between
words.
Right and left justification can
cause odd spacing between
words.
Figure 10.6 Odd spacing created in justified text can sometimes be
improved by changing the width of the text box.
The poster title and section headings are the only appropriate place for most other
, ALL CAPS), because they generally
text effects (e.g., italics, shadow,
make the text more difficult to read.
Text justification (i.e., alignment) must also be considered. For many years,
scientists preferred to leave the right edge unjustified or jagged. With word
processing, however, justified text (like a newspaper column that is aligned on
both the left- and right-hand margins) has become more common. In a poster,
it is common to see large blocks of text (e.g., the Introduction section) justified, and short sections of text (e.g., bulleted lists) left-justified (jagged on the
right). If you use full justification (i.e., left and right edges), look out for odd
spacing between words. Awkward spacing can usually be fi xed by changing the
column width, as shown in figure 10.6, where the problem is solved by widening the column. If changing the width does not work, consider using leftjustified text.
Justification
Justification refers to the alignment of the left and right edges of the text.
Whether to align both the right- and left-hand margins (“justified”) or leave the right
margin jagged (“left-justified”) is a matter of taste, although justified text is becoming more
common.
10B Designing on Your Own: Choose a Font and Font Size
Experiment with the font style and font sizes for your poster. Choose a style that is easy
to read and large enough to see from 5 feet (1.5 m) away. Continue to revise your text as
needed to accommodate the layout, font(s), and font sizes selected.
One hint for working with text: Use text boxes rather than placing your text directly into
the poster. Text boxes make the text easier to move around and to resize, if needed.
Designing the Poster
347
Analyzing Color and Artwork
Color is potentially the most useful tool for creating an effective and aesthetically
pleasing poster, but it is also the most subjective. As with layout and font, colors
should be chosen to help communicate your scientific message. Follow these few
simple guidelines:
348
■
Use contrast: Make sure that your text contrasts sharply with the background. You may use the traditional approach, a dark text on a light background, or an inverted color scheme, light text on a dark background.
If you use an inverted color scheme, consider using larger font sizes; the
dark background tends to encroach on light letters, making them appear
smaller.
■
Avoid red and green: Most colorblind individuals cannot distinguish red and
green. Avoid using red text on a green background (or vice versa) and red
and green in graphs.
■
Include text boxes: If you want a dark background, you can still achieve good
contrast with dark text by placing text in “boxes” filled with a light color. The
borders of the boxes can be rounded or square, depending on the effect that
you are trying to achieve.
■
Limit yourself to three or four colors: Use colors consistently throughout your
poster (i.e., use one color for text, one color for backgrounds, one color for
borders, etc.).
■
Use conservative colors for the majority of your poster; save bright colors for
accents and highlights.
■
Use color to enhance your science: Colors should facilitate understanding,
be clearly distinguished, and, when possible, convey meaning (e.g., blue
for water, red for heat). Create a “color code” for your own consultation and
use it consistently throughout the poster. For example, if you use blue and
gray to represent compounds 1 and 2 in your first graph, use blue and gray
for these compounds in additional graphs. Readers will grow accustomed
to what each color represents and will be able to interpret your poster more
quickly.
■
Minimize background distraction: The background color or graphic
should not overpower the text or distract viewers from the scientific
content. For a brief period of time, blurred and faded images were popular
for poster backgrounds, but too often they interfered with the text. Now
consensus favors a one-color, solid background, although shading is
sometimes used.
■
Preprint your poster to check colors: Remember that the colors that you
view on your computer screen often look different when printed; print a
small-scale color draft of your poster before you print the full-scale version.
The Scientific Poster
Inverted Color Scheme
An inverted color scheme uses light letters on a dark background. Because dark backgrounds appear to “shrink” light letters, use larger font sizes for inverted color schemes.
Posters may also contain different types of illustrative artwork, such as photographs, maps, and logos. When used appropriately, artwork can greatly enhance the
visual appeal of the poster and add to the viewer’s understanding of the research.
Photographs of equipment, a field-sampling site, or even scientists performing
a particular technique are all appropriate and commonplace in posters. Maps are
also common, illustrating the location of a research study. Finally, small color logos
can be placed near the title or Acknowledgments section of posters to indicate the
researchers’ institutions and funding sources, respectively. Logos should not be used
in place of text; rather, they should be used to reinforce what is stated in the text.
Logos
Logos are commonly included in titles and Acknowledgments sections of posters.
It is important to distinguish between scientific graphics and artwork. Scientific
graphics (figures, tables, charts) should be mentioned in the text (e.g., “Figure 1”) and
include a title or caption, just as they would in a journal article or research proposal.
Illustrative artwork, however, can be left “dangling” (i.e., included without being
mentioned in the text). Photographs may fit into either category, depending on their
content. If an instrument, site, or technique is featured in the photograph, it should
have a caption and should be referenced in the text. A photograph of a research
group, research building, or familiar campus landmark can be left dangling.
To conclude this section and chapter, we present three sample posters (figures
10.7–10.9) created from text developed in chapter 9 and design elements discussed
in this chapter. (See also figure 9.1 in chapter 9 for a fourth sample poster.) Table 10.3
summarizes some of the design elements of these posters. Full-color versions of
these posters are available at the Write Like a Chemist Web site. Together, we hope
that these four posters stimulate ideas for preparing your own poster.
Designing the Poster
349
350
Figure 10.7 The final design of the poster based on Llompart et al. (2001).
Figure 10.8 The final design of the poster based on Vesely et al. (2003).
Figure 10.9 The final design of the poster based on Boesten et al. (2001).
Table 10.3 Selected design elements in sample posters. Fonts include Arial (Ar), Book Antiqua (BA),
Comic Sans MS (CS), Tahoma (Th), and Times New Roman (TNR). Posters are 36 in. tall 56 in.
wide (~91 cm 142 cm).
Design Element
Figure 9.1
Figure 10.7
Figure 10.8
Figure 10.9
Title
Ar 136 bold
CS 100 bold
Ar 112 bold
Th 100 bold
Author list
Ar 60 bold
CS 50 bold
Ar 72 bold
Th 60 bold
Affiliation
Ar 50 bold
CS 50 bold
Ar 60
Th 60
Headings
CS 72 bold
BA 72 bold
Ar 72 bold
Th 72 bold
Text
Ar 36
BA 36
TNR 36
Ar 39
Layout
column
column/row
column
column
Color, background
orange (border)
dark red
white
dark blue
Color, text boxes
white
cream
none
none
Color, text
black
black
dark blue
white/yellow
Alignment, Introduction
left-justified
left-justified
justified
justified
Exercise 10.3
Analyze the black-and-white posters in figures 9.1 and 10.7–10.9. Evaluate layout,
font, and font size. Then view the color versions of the posters on the Write Like a
Chemist Web site. How does color further enhance poster impact?
10C Designing on Your Own: Add Color and Artwork
Now that your poster design is almost complete, you can experiment with a color scheme.
Try several different combinations of colors until you find one that is pleasing and easy to
read. Make sure that the colors you select enhance your poster rather than distract the
viewer from the scientific content. Choose poster and text backgrounds that enhance the
readability of your poster. Decide whether there are any additional graphics, such as logos
and photos, that you would like to add to your poster.
Exercise 10.4
The Write Like a Chemist Web site includes six sets of “initial” and “revised”
student posters. Glance at these posters. Based on what you have learned in
this chapter, identify at least three improvements that have been made in each
revised poster. Suggest at least three additional improvements that could still
be made.
Designing the Poster
353
10D Designing on Your Own: Finalize Your Poster
Before you print a final version of your poster, revise and edit your poster as a whole. We
recommend that you reread and edit your poster, focusing on each of the following areas:
1. Organization: Check your overall organizational structure. Did you follow the move
structures that were suggested in chapter 9? Is each section of the poster easy to identify? Does each section contain appropriate headings and information?
2. Audience, conciseness, and fluency: Verify that your poster addresses the correct
audience. Is your poster crisp and uncluttered, leaving out unnecessary details? Could
some of the content be presented in a bulleted list of phrases rather than in complete
sentences?
3. Science content: Are you prepared to discuss your poster with an expert audience?
Have you correctly conveyed the science in your work? Have you used words and
units correctly? If asked, could you define all of the words that you have used in
your poster?
4. Writing conventions: Check to be sure that you have followed poster writing conventions, including the use of abbreviations, bulleted fragments, lists, and citations.
5. Grammar and mechanics: Check for typos and errors in spelling, subject–verb agreement, and punctuation. Be sure that you have used troublesome words such as effect,
affect, and data correctly.
6. Visual design: Consider the overall appearance of your poster. Is it easy to read?
Will a reader be able to naturally follow the flow of your poster? Is it free of distracting,
unnecessary graphics? Have you used fonts and colors in a consistent manner?
Finalizing Your Poster
See chapter 18.
Chapter Review
As a self-test of what you’ve learned in this chapter, define each of the following terms, in the context of the chapter, for a friend or colleague who is new to
designing posters:
354
column layout
inverted color scheme
row layout
dangling graphics
justification
sans-serif font
flow
logos
serif font
The Scientific Poster
As a follow-up self test, explain the basic principles governing these aspects of
poster design:
■
Layout
■
Fonts and font sizes
■
Colors
Additional Exercises
Exercise 10.5
Reflect on what you have learned about designing a scientific poster. Select one of
the reflection tasks below and write a thoughtful and thorough response:
a. Reflect on the poster as a visual display of information.
■
■
■
■
Which visual features (e.g., bullets, colors, font sizes, graphics, layout,
photographs) seem to be most important for flow?
Which visual features seem to be most important for the clear, unambiguous presentation of information?
Which visual features are most likely going to draw viewers in?
Which visual features might distract readers, thus the need for care in
using (or avoiding) them?
b. It was stated early in the chapter that the goal of a poster is to present your
science in a way that is clear, crisp, and uncluttered.
■
■
■
What layout principles allow for a clear presentation?
What layout principles allow for a crisp presentation?
What layout principles allow for an uncluttered presentation?
c. Reflect on the similarities and differences between a journal article and
poster.
■
■
■
Designing the Poster
Consider the two genres in terms of audience, organization, and writing
conventions.
Consider the two genres in terms of scientific content.
Consider the two genres in terms of visual presentation.
355
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Module 3
The Research Proposal
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11
Overview of the Research Proposal
The primary purpose of reports and articles is to inform;
the primary purpose of proposals is to persuade. Your goal
in proposal writing is not just to inform your audience about
a solution to a problem, but to convince your audience
to give you funds so that you can solve a problem.
—Adapted from Alley (1996)
In this module, we focus on writing a research proposal, a document written to request fi nancial support for an ongoing or newly conceived research
project. Like the journal article (module 1), the proposal is one of the most
important and most utilized writing genres in chemistry. Chemists employed
in a wide range of disciplines including teaching (high school through university), research and technology, the health professions, and industry all face
the challenge of writing proposals to support and sustain their scholarly
activities.
Research Proposal
A document written to solicit financial support for an ongoing or new research
project.
Research proposals, sometimes referred to by the more generic term grant proposals,
are written to solicit a research grant.
Before we begin, we remind you that there are many different ways to write
a successful proposal—far too many to include in this textbook. Our goal is not
to illustrate all the various approaches, but rather to focus on a few basic writing
skills that are common to many successful proposals. These basics will get you
started, and with practice, you can adapt them to suit your individual needs. After
reading this chapter, you should be able to do the following:
■
Describe different types of funding and funding agencies
■
Explain the purpose of a Request for Proposals (RFP)
■
Understand the importance of addressing need, intellectual merit, and
broader impacts in a research proposal
■
Identify the major sections of a research proposal
■
Identify the main sections of the Project Description
Toward the end of the chapter, as part of the Writing on Your Own task, you will
identify a topic for the research proposal that you will write as you work through
this module.
Reading and Analyzing Writing
Consistent with the read-analyze-write approach to writing used throughout
this textbook, this chapter begins with an excerpt from a research proposal for
you to read and analyze. Excerpt 11A is taken from a proposal that competed
successfully for a graduate fellowship offered by the Division of Analytical
Chemistry of the American Chemical Society (ACS). As is true for nearly all
successful proposals, the principal investigator (PI) wrote this proposal in
response to a set of instructions. We have included the instructions with the
excerpt so that you can see for yourself how closely she followed the proposal
guidelines.
Principal Investigator
The principal investigator (PI) is the main author of a proposal. Additional authors are
termed co-principal investigators (co-PIs).
Exercise 11.1
Read excerpt 11A. First read the Program Description and Proposal Instructions,
and then read the proposal excerpt. How well does the author follow the
instructions? Comment briefly on the excerpt in terms of its audience and purpose, organization, writing conventions, grammar and mechanics, and science
content.
360
The Research Proposal
Excerpt 11A
Graduate Fellowship Announcement (adapted from the ACS Division of Analytical
Chemistry Graduate Fellowship announcement. http://www.wabash.edu/
acsgraduatefellowship/ (accessed May 31, 2005))
Program Description
■
The purposes of these Fellowships are to encourage basic research in the field of
analytical chemistry, to promote the growth of analytical chemistry in academic
institutions and industry, and to provide recognition of future leaders in the field of
analytical chemistry.
■
The Graduate Fellowship Committee of the ACS Division of Analytical Chemistry,
which evaluates the applications and makes the fellowship awards, comprises representatives from the sponsoring companies, analytical faculty from undergraduate
institutions, and scientists from national laboratories.
■
The student applicant must be a full-time student working toward a Ph.D. in analytical chemistry and must have completed the second year of graduate study by the
time the fellowship period begins.
Proposal Instructions
IN NO MORE THAN TWO PAGES attached to this application, (1) provide your thesis
title, (2) summarize the objectives of your thesis, (3) summarize work already accomplished, (4) summarize work planned for the term of the fellowship, and (5) explain the
relevance of your work to analytical chemistry.
Research Proposal Excerpt (from a successful proposal submitted for this award:
Haes, 2003)
Thesis Title and Objectives. The current title of my thesis is “The Characterization
and Development of the Localized Surface Plasmon Resonance Nanosensor.” The overall
goal of my thesis work is to elucidate the sensing mechanism of the localized surface
plasmon resonance (LSPR) of triangular Ag nanoparticle biosensors and to apply that
knowledge to optimize their use as a novel analytical tool. The combination of UV–vis
spectroscopy and surface-enhanced Raman scattering (SERS) will allow for high
throughput general analyte screening and specific analyte identification, respectively.
The individual objectives leading to my overall goal include the following: (1) systematically study the short-range behavior of alkanethiol self-assembled monolayer adsorbates
on nanosphere lithography (NSL) derived Ag nanoparticles in order to maximize the
LSPR response for a single adsorbate, (2) systematically study the long-range behavior of
multilayer adsorbates on various sized and shaped NSL derived nanoparticles, (3) investigate the model system of streptavidin binding onto biotinylated Ag nanoparticle sensors, (4) determine the level of nonspecific binding interactions of the LSPR nanosensor
response, (5) perform an immunoassay using anti-biotin on biotinylated Ag nanoparticles, (6) systematically study how the LSPR nanosensor responds to resonant molecules
by varying the extinction maximum (that is, produce on and off resonance conditions)
Overview of the Research Proposal
361
of Ag nanoparticles, (7) attach cytochrome P450 (cyt P450) to the surface of Ag nanoparticles to study their interactions with drug molecules, (8) engineer a microfluidic chip
to decrease analyte solution volumes, and (9) combine the high throughput screening of
the LSPR nanosensor with SERS for chemical identification.
Background and Summary of Accomplished Work. Before I entered graduate
school, the Van Duyne group had already demonstrated that NSL is a simple, inexpensive, and versatile technique for the fabrication of nanoparticles1 and that NSL-derived
Ag nanoparticles could be used as biological and chemical optical nanosensors by
monitoring the maximum LSPR peak extinction wavelength.2 Since joining the group,
additional progress has been made on Objectives 1–6. For example, Objective 1, which
measures the short range (viz., 0–2 nm) distance dependence of the electromagnetic
fields that surround resonantly excited Ag nanoparticles, has been tested. Results
indicate that the response is linear and can be systematically tuned by changing the
structure and composition of the Ag nanoparticles.2,5 . . . The long range distance dependence of the LSPR of noble metal nanoparticles (Objective 2) has also been elucidated.5
Measurement of the LSPR extinction peak shift versus number of layers and adsorbate
thickness is non-linear and has a sensing range that is dependent on the composition,
shape, in-plane width, and out-of-plane height of the nanoparticles. This remarkable set
of experiments confirms that the sensing capabilities of noble metal nanoparticles can
be tuned to match the size of biological and chemical analytes by adjusting the aforementioned properties. The optimization of the LSPR nanosensor for a specific analyte
will improve an already sensitive nanoparticle-based sensor.
. . . [Section omitted that describes work toward Objectives 3–5]
To date, all LSPR nanosensor experiments have been performed using non-resonant
molecules. Because the effect that molecular resonances have on nanoparticle sensing
is unknown, my current studies are aimed at answering this question (Objective 6).
Preliminary results indicate that the resonant molecule, Fe(bpy)32 (bpy 4,4-bipyridine), dramatically enhances the sensitivity of the LSPR nanosensor when the extinction
maximum of the nanoparticles is slightly red-shifted from the molecular resonance.
Planned Research for the Duration of the ACS Analytical Fellowship. During the
remainder of my graduate school career, I will concentrate on completing the aforementioned resonant molecule studies and on fulfilling my final three thesis objectives:
attaching cyt P450 (a resonant molecule) to Ag nanoparticles in order to study their
interactions with drug molecules, engineering a microfluidic chip to decrease analyte
solution volumes, and combining the high throughput screening of the LSPR nanosensor
with SERS for chemical identification. These accomplishments will allow the objectives
of my thesis to be fulfilled and will aid in the development of a more powerful biosensor,
a useful analytical tool.
The motivating factor behind my current studies with Fe(bpy)32 is to best design
a sensor surface for cyt P450 modification. Like Fe(bpy)32 , cyt P450 has a molecular
resonance in the visible region of the electromagnetic spectrum. The cyt P450 family
of enzymes participates in the metabolism of a large fraction of all drugs in medicine.
Interactions with cyt P450 enzymes are often the major limitation of a drug’s usefulness. To optimize the LSPR nanosensor for drug screening using cyt P450 functionalized
362
The Research Proposal
nanoparticles, the role molecular resonances have on the LSPR sensing mechanism must
be better understood.
One of the characteristics of the LSPR biosensor is its generality. This is a powerful
attribute for fast, high throughput screening of adsorbates, but, at times, specific analyte
identification is needed. SERS, an extremely sensitive analytical tool, yields detailed
chemical and conformational information of adsorbates near roughened noble metal surfaces.8 SERS signals are generally 106 times larger than normal Raman signals. Because
NSL-derived Ag nanoparticles exhibit large SERS enhancements, the combination of
UV–vis and SERS will produce a biosensor capable of both high throughput screening
and exact chemical identification.
Relevance to Analytical Chemistry. The relevance of my work to analytical chemistry is apparent on two levels. First, the understanding of metal particles in the nanoregime is not fully understood. Additionally, many chemical processes occur in this size
scale. Clearly, this research advances that knowledge. Second, the analytical technique
of biosensing is the practical application of this work. Our results suggest that in the
near future Ag nanotriangle biosensors could be used for the detection of a wide variety
of biomolecules. Binding of DNA, proteins, and possibly eukaryotic cells (by using protein ligand intermediates) to noble metal nanoparticles opens a window of opportunity
in medical diagnostics and could greatly simplify often tedious immunohistochemical
detection tasks performed regularly in biomedical research. Future work on miniaturization of the sensor, linkage of the sensor to drug delivery chips, and biocompatibility
could make this laboratory-based device into a portable analytic and diagnostic tool.
Finally, by combining the powerful techniques of LSPR screening and SERS identification on a microscale system, new limits to chemical and biological sensing processes
will be reached.
Affect vs. Effect
See appendix A for more information on these commonly confused words.
Several features are worth noting in excerpt 11A. First, consider the Proposal
Instructions. In addition to a title, the instructions ask for (in no more than two
pages) a statement of project objectives, a summary of previous work, a description of the proposed work, and an explanation of why the work is relevant. These
four items typify the content requested in most proposals. Second, consider the
proposal itself. What writing components did you notice as you read the excerpt?
Below we highlight some of the components that are addressed in this module.
Additional features are highlighted in exercises 11.2–11.8.
■
Audience and purpose: Haes writes her proposal for an expert audience.
The proposed work is in a specialized subfield of analytical chemistry
(nanosensors), and she assumes that her readers are knowledgeable in
Overview of the Research Proposal
363
this area. For example, terms such as localized surface plasmon resonance
and nanosphere lithography are used without defi nition. The Program
Description states that evaluators are “representatives from the sponsoring companies, analytical faculty from undergraduate institutions, and
scientists from national laboratories”; hence, the author has targeted the
right audience. We will see, however, that not all proposals are written
for an expert audience and, in many proposals, more than one audience is
targeted.
■
Organization: Haes closely follows ACS guidelines and uses subheadings
that directly correspond to points 1–5 in the Proposal Instructions (a practice that we highly recommend). She begins by describing the broad goal
of the research project and then enumerates the individual objectives that
lead to that goal. She delineates work that has already been accomplished,
as well as work that remains to be done. The proposal concludes by
emphasizing why this work is relevant to the field of analytical chemistry. Her proposal mirrors the general organizational structure of many
proposals.
■
Writing Conventions: Haes uses predominantly present tense, present perfect, and future tense. Present tense is used for project goals and objectives
and for knowledge believed to be true over time; present perfect is used for
work conducted in the past; future tense is used for work to be done in the
future. Haes also uses personal pronouns in her proposal (e.g., “my thesis
work”, “our results”, and “before I entered graduate school”). Her use of
personal pronouns and verb tenses follows writing conventions common in
research proposals. Haes also makes use of enumerated lists in her proposal.
Most chemists agree that this is an effective and space-saving formatting
technique; hence, lists are commonplace in proposals.
■
Grammar and mechanics: Haes pays careful attention to parallelism and
punctuation, most notably in her enumerated lists. Haes’s lists are grammatically parallel, and she uses punctuation (i.e., colons, commas, and semicolons) appropriately.
Present Perfect
See table 6.2.
Exercise 11.2
Look for the following formulas, abbreviations, and acronyms in the proposal in
excerpt 11A: Ag, SERS, UV–vis, cyt, and bpy. Which are defined at first use, and
which are not? Are these choices correct? Explain.
364
The Research Proposal
Exercise 11.3
Research proposals often make use of two related words: goals and objectives.
Describe how Haes uses these two words in her proposal. Are the terms used
consistently throughout?
Exercise 11.4
Consider passages 1–4 below, taken from the Haes proposal:
a. Two of the four passages depict moves commonly encountered in journal articles. Match the two passages with their correct move(s), choosing
from the following: (1) introduce topic/purpose, (2) present background
information, (3) identify a gap, (4) fi ll a gap, and (5) describe experimental
methods.
b. The remaining two passages depict new moves (i.e., moves not listed in 11.4a).
Which passages are they? Suggest the purpose(s) of these passages, thereby
identifying new moves.
1. Because the effect that molecular resonances have on nanoparticle sensing is unknown, my current studies are aimed at answering this question
(objective 6).
2. Preliminary results indicate that the resonant molecule, Fe(bpy)32 (bpy 4,4-bipyridine), dramatically enhances the sensitivity of the LSPR nanosensor when the extinction maximum of the nanoparticles is slightly redshifted from the molecular resonance.
3. Like Fe(bpy)32 , cyt P450 has a molecular resonance in the visible region
of the electromagnetic spectrum. The cyt P450 family of enzymes participates in the metabolism of a large fraction of all drugs in medicine.
4. The overall goal of my thesis work is to elucidate the sensing mechanism
of the localized surface plasmon resonance (LSPR) of triangular Ag nanoparticle biosensors and to apply that knowledge to optimize their use as a
novel analytical tool.
Exercise 11.5
The following two sentences use colons, commas, and/or semicolons incorrectly;
correct the mistakes:
a. The techniques include: (1) GC/MS; (2) UV–vis spectroscopy; and (3) NMR
spectroscopy.
b. Several techniques were used: (1) GC/MS, (2) IR, UV, or UV–vis spectroscopy, and (3) NMR spectroscopy.
Overview of the Research Proposal
365
Colons, Commas, and Semicolons
See appendix. A.
Exercise 11.6
Consider the following passage from a section in Haes’s proposal, omitted from
excerpt 11A. We have removed all colons, semicolons, and commas from the
passage. Decide which form of punctuation belongs in each empty space or if the
space should remain blank.
The hexadecanethiol (HDT) induced LSPR peak shift for Ag nanotriangles as a function
of structure has been determined ___ (1) HDT sensitivity decreased by 0.11 and 0.52 nm
per nm increase in in-plane width at fi xed out-of-plane heights of 50.0 and 30.0 nm ___
respectively ___ (2) HDT sensitivity increased by 0.33 nm per nm increase in out-ofplane height at fi xed in-plane widths of 100 nm ___ (3) HDT sensitivity was 1.5 times
larger for chopped tetrahedra than for hemispheres with equal volumes ___ and (4) HDT
sensitivity of Ag nanotriangles was 3.5 times larger than Au nanotriangles with identical
in-plane widths and out-of-plane heights.
Exercise 11.7
Find one sentence in the proposal in excerpt 11A that illustrates each of the
following:
a. The correct use of present tense to describe the goal(s) and objective(s) of the
proposed work.
b. The correct use of present tense to describe knowledge (or findings) expected
to be true over time.
c. The correct use of present perfect for work done in the past.
d. The correct use of future (with will) to describe future work.
Exercise 11.8
Each of the following sentences includes a list or series that is not parallel. Revise
the sentences so that the lists or series within them are parallel.
a. The method we now describe for deducing the individual J values from
any first-order multiplet requires two principal operations: (1) to assign
each of the individual 2 components (cf. Figure 1) and (2) systematic
366
The Research Proposal
identification of the individual J values.5 (Adapted from Hoye and Zhao,
2002)
b. Specific particulate-associated diseases implicated by these studies include
the exacerbation of asthmatic episodes, the induction of chronic bronchitis,
and causing the induction of interstitial fibrosis. (Adapted from Kristovich
et al., 2004)
c. However, during incineration, the following major problems were encountered: (1) excessive bed temperature, (2) frequent clinker formation, (3) flue
gases reaching high temperatures, and (4) excessive pressure drop. (Adapted
from Shie et al., 2004)
Parallelism in Lists
Lists should be parallel in language, numbering, punctuation, and formatting. (See
appendix A.)
Selecting a Funding Agency and RFP
The most important criteria for all proposal writing are the explicit
instructions in the RFP.
—Paradis and Zimmerman (1997)
The first step in writing a successful proposal is to select a funding agency. This
is no easy task. The number of funding sources is mind-boggling and includes
federal, state, and local government organizations, as well as public and private
corporations, foundations, and individuals. To begin to appreciate the range of
possibilities, browse through the funding opportunities listed on the Web pages
of the ACS, USDA, EPA, NIH, or NSF. Or, if you have a specific topic, create a
list of keywords and search for them using searchable databases such as www.
grants.gov (a free portal site to more than 1,000 federal grant-making agencies)
or the Illinois Researcher Information System, IRIS (a fee-based site to more than
8,600 federal and private funding agencies in the sciences, social sciences, arts,
and humanities). You can also search online using Google.com or other Internet
search engines. (If you use Google, try placing quotation marks around the searchable terms and add (without quotation marks) “ grant” following the terms. E.g.,
if you are searching for grants on water pollution, you might try the following:
“water pollution” grant.)
Overview of the Research Proposal
367
Abbreviations for Funding Agencies
Many funding agencies have abbreviated names. Here are five used in this textbook:
ACS: American Chemical Society
USDA: U.S. Department of Agriculture
EPA: Environmental Protection Agency
NIH: National Institute of Health
NSF: National Science Foundation
To navigate this complex world of funding successfully, it helps to seek advice
from others. Whenever possible, talk with individuals at your institution (e.g.,
peers, colleagues, or research mentors) who have received grants that match your
particular research interests or funding needs or who are familiar with the funding process (e.g., grant officials). Find out what worked for them. Here are a few
additional guidelines to help you in the agency-selection process:
■
Look for internal funding first (funding from within your institution), as opposed
to external funding. Many institutions offer competitive internal awards for
undergraduate and graduate students. Such awards often provide a research
stipend and may also offset expenses for tuition, books, travel (to conferences or
field sites), and/or laboratory supplies. For faculty, internal funding may serve as a
stepping stone to external funding (and is sometimes called “seed” money).
■
Look for funding opportunities that target researchers like you (e.g., undergraduate- or graduate-level students, beginning faculty members, non-U.S.
citizens, members of an underrepresented population).
■
Look for funding opportunities that target your specific need (e.g., a summer
research fellowship, a travel grant, a new piece of equipment).
■
Look for funding opportunities that match your project goals. Some grants
support fundamental research, research that targets new insights and
knowledge (e.g., the ACS Graduate Fellowship described in excerpt 11A).
Other funding agencies target more applied research, research designed to
solve a specific problem.
Internal and External Funding
Internal funding originates in your home institution; proposals are evaluated by anonymous internal reviewers.
External funding originates outside your institution (e.g., the NSF); proposals are judged by
anonymous external reviewers.
368
The Research Proposal
Fundamental and Applied Research
Fundamental research attempts to uncover scientific principles and the laws of
nature.
Applied research uses acquired knowledge to solve problems.
After you have narrowed your search to a specific agency and grant, the next
step is to read in detail the grantor’s instructions for the application process.
Such instructions are typically included in a Request for Proposals (RFPs) or
Request for Applications (RFAs). RFPs will vary in length from a few paragraphs to more than 10 pages; regardless of length, these documents are your
most valuable resource for writing a proposal. The RFP will help you organize your proposal, format it correctly, and address the specific needs of your
funders. Because of their importance, we examine several RFPs in this chapter
and use them to guide our discussion of how to write a proposal (here and in
chapters 12–15).
RFPs and RFAs
RFP: Request for Proposals
RFA: Request for Applications (another term for RFPs)
Exercise 11.9
Browse through the grant and funding opportunities listed on the Web site of a
large institution, such as the NSF, NIH, ACS, or EPA, and complete the following
tasks:
a. Determine if there are funding opportunities that target specific researcher
populations (e.g., undergraduate or graduate students, new faculty, underrepresented populations).
b. Determine if there are funding opportunities that target a specific need (e.g.,
summer research fellowships, travel grants, equipment grants).
c. Identify five areas of research that the agency will fund. If possible, classify
each area as fundamental or applied research.
d. Locate the RFP for one funding opportunity. Browse through the RFP.
Compare this RFP to the Proposal Instructions in excerpt 11A for the ACS
Graduate Fellowship in Analytical Chemistry.
Overview of the Research Proposal
369
Writing a Persuasive Proposal
After you have selected a funding agency and read the RFP, the task of writing the
proposal is at hand. Before you begin, keep in mind that your proposal must be
persuasive. Think of yourself as an entrepreneur asking others to invest in your
project; your proposal must convince them to give you money. It is not enough
to limit your persuasive remarks to a single paragraph or section of the proposal;
your proposal should be compelling throughout. This can be accomplished by
using different persuasive tactics throughout your proposal. Collectively, the tactics involve persuading your funders that your proposed work
■
meets their needs
■
has intellectual merit
■
has broader impacts for society
We look briefly at each tactic below (abbreviated as need, intellectual merit,
and broader impacts) and consider them again as we work through the various
sections of the proposal.
Need
Your research idea must overlap with a need that the funding agency has identified. Funding will be denied—or worse, the proposal will be returned unread—if
the needs of the funding agency are not addressed. The need is often suggested
in the RFP title and spelled out in the RFP text. The RFP may also refer you to a
Web site with the agency’s mission statement, strategic plan, or rationale for the
current funding initiative. Read these documents! Knowledge of the agency’s mission allows you to align your research interests and goals with theirs.
Exercise 11.10
Consider the following RFP titles for EPA grants offered in 2006. What need is
addressed in each title? How does each need fit into the overarching mission of
the EPA, which is to protect human health and the environment?
370
■
Allergenicity of Genetically Modified Foods
■
Ecological Impacts from the Interaction of Climate Change, Land Use
Change, and Invasive Species
■
Sources, Composition, and Health Effects of Coarse Particulate Matter
■
Fate and Effects of Hormones in Wastes from Concentrated Animal Feeding
Operations
The Research Proposal
Intellectual Merit
When I was Program Officer at the National Science Foundation,
I witnessed without a doubt that simply and clearly written proposals
sailed through more easily than ones that were not so. Surely there is
a lesson there.
—Robert Damrauer, University of Colorado–Denver
It is not enough that your proposal targets the needs of a funding agency; your
proposed idea(s) must also be intellectually sound. Typically, reviewers judge
the intellectual merit of a proposal according to three criteria, each of which is
described in more detail below:
■
the creativity of your ideas
■
the credibility of your work plan
■
your competence as a researcher
Three C’s
Creativity
Credibility
Competence
Demonstrate your intellectual merit in a research proposal by emphasizing the three C’s.
Proposals score high points if they present a creative approach or an innovative idea. A good idea that has already been explored, by you or by others, is
seldom funded. A winning proposal must demonstrate that the proposed work
will accomplish something new. Gap statements and gap-fillers, as in journal
articles (see chapter 6), are used in research proposals to call attention to the new
steps that your proposed work will take. By addressing problems that were left
unsolved in the past, and by showing how your new approach will solve them,
you underscore the creativity of your work.
Gap Statements
See table 6.1.
Intellectual merit is also based on the credibility of your work plan, including both the proposed research methods and projected timeline. To be credible,
Overview of the Research Proposal
371
your proposed methods must be sound. Knowledge of standard techniques must
be evident (in the text and/or through citations to the literature), even if you are
proposing a new or innovative approach. Credibility is also enhanced by describing the inherent limitations of your methods (e.g., by including error bars, detections limits, or the range over which a calibration is accurate). Timelines should
be ambitious but realistic. If you are an undergraduate student, you are likely to
underestimate how long your project will take. Consult your research mentor for
ideas about realistic timelines.
Writing and Science
Writing skills cannot replace good science, but writing skills are needed to convey good
science. Your competence as a scientist will be judged, in large part, by your writing.
Your competence to do the proposed work is also evaluated. Competence is
judged largely by your past achievements (thus, the importance of doing excellent
work if you receive a research grant). Early in your career (e.g., as an undergraduate or graduate student), transcripts, test scores, and letters of recommendation
are used to judge your competence. As you progress in your career, your competence is judged by your level of education, work history, publications, grants
received, conferences presentations, and other scholarly contributions.
Intellectual merit is also judged by your writing ability (hence the reason for
including this module in our textbook). The value of a well-written proposal cannot be overstated. An articulate and clearly organized proposal promotes the original qualities of your work and convinces readers that you can carry out the work
described. It is not an exaggeration to say that your competence as a scientist
will be judged by your writing. A competent scientist pays attention to detail; a
carelessly written proposal that includes typos, poor organization, and confusing
sentence structure leaves a negative impression and undermines any confidence
readers might have had with the author. Thus, although writing skills cannot
replace good science, writing skills are needed to convey good science.
Broader Impacts
A creative but excessively narrow proposal has limited chances of being funded.
Proposals that demonstrate the potential for contributions to a greater good
and the advancement of future scientists’ knowledge are likely to be supported.
Minimally, you should explain how your work will benefit other scientists (both
within your discipline and in general); optimally, you should explain how your
work will benefit society at large. Importantly, broader impacts must be spelled
out in language that a general audience can understand. Granting officials often
372
The Research Proposal
use your words to share your ideas with potential donors and the general public. Hence, the burden is on you to express your science in a way that is easily
understood.
Broader Impacts
In this textbook, the term broader impacts refers to how your proposed work will benefit
other scientists, society at large, and the training of future scientists.
Another broader impact of research is the training and education of future
scientists. Trained scientists are a national (and international) resource; research
activities create a “pipeline” of individuals—undergraduate, graduate, and postdoctoral researchers—to renew this resource. Ideally, this pipeline reflects the
ever-changing composition of society. To this end, federally funded programs
(e.g., the NSF) now require that investigators describe how their research activities will add to this pipeline by training new scientists and encouraging participation by underrepresented groups. In this way, funding initiatives advocate the
development of not only new science but also new scientists.
Exercise 11.11
Glance at an RFP for a research grant. Use an RFP provided by your instructor
or search for a funding agency on the Web such as the EPA, NIH, NSF, Research
Corporation, or the ACS Petroleum Research Fund.
a. Describe the activities that the grant will fund.
b. Identify whether the grant targets fundamental or applied research.
c. Describe how the RFP addresses issues related to need, intellectual merit,
and broader impacts.
Addressing need, intellectual merit, and broader impacts are essential for a successful proposal. The converse is also true; proposals that lack these qualities are
unlikely to be funded. Bowman and Branchaw (1992) corroborated this assertion by compiling a list of the most common reasons why proposals are rejected
(table 11.1). As you glance through the list, note how many reasons link back
to need, intellectual merit, and broader impacts. Note, too, that proposals are
rejected because they are not submitted on time and do not follow RFP guidelines. Paying careful attention to “picky” requirements such as page length and
formatting is essential. An improperly formatted proposal immediately suggests
Overview of the Research Proposal
373
Table 11.1 Common reasons for the rejection of research proposals (adapted from
Bowman and Branchaw, 1992).
(a)
The author did not demonstrate a clear understanding of the problem.
(b) The proposal did not arrive by the submission deadline.
(c)
The information requested in the RFP was not provided.
(d) The objectives were not well defi ned.
(e)
The wrong audience was addressed.
(f)
The procedures and methodology were not specific.
(g) The overall design was questionable.
(h) Cost estimates were not realistic: either too high or too low.
(i)
Resumes of key personnel were inadequate.
(j)
Personnel lacked experience or the required qualifications.
(k) The proposal was poorly written and not well organized.
(l)
The proposal did not follow the organizational pattern specified in the RFP.
(m) The proposal did not provide adequate assurance that completion deadlines would
be met.
(n) Essential data were not included in the proposal.
(o)
The proposed time schedule was unrealistic.
(p) The project objectives were not clearly linked to an agency-based need.
(q)
The author did not adequately address why this project is important or how it will
contribute to society at large.
that you are incapable of carrying out a well-organized, disciplined research
project.
Exercise 11.12
Review the list in table 11.1. Identify reasons for the rejection of research proposals that link directly to the following:
a. the authors’ failure to address need (identified by the funding agency)
b. the authors’ failure to establish intellectual merit (creativity, credibility, and
competence)
c. the authors’ failure to address broader impacts
d. the authors’ writing skills
e. other
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The Research Proposal
Selecting an Audience
A successful proposal must also target the proper audience. For proposals, the
audience typically comprises a panel of preselected reviewers. The task of the
reviewers is to read and score the submitted proposals. Because the background
and training of panel members will vary from proposal to proposal, you must
consult the RFP for information about who your reviewers will be. For example, in excerpt 11A, the Program Description states that the reviewers will be
“representatives from the sponsoring companies, analytical faculty from undergraduate institutions, and scientists from national laboratories.” As a result, the
author wrote her proposal largely for an expert audience. If, however, you are
an undergraduate writing a proposal to support your undergraduate research,
your audience will be much different. Undergraduate research awards are typically reviewed by a broad cross section of faculty, including faculty from both the
physical and social sciences. In this case, you should introduce your ideas at a scientific or even an “advanced” general audience level. If sociology professors learn
some chemistry while reading your proposal, all the better. They will be inclined
to regard your proposal more highly, and they will trust that you understand the
proposed work, an essential prerequisite for funding.
If the audience is not clearly defined in the RFP, we recommend a two-tiered
approach. When you introduce your ideas and describe the importance of your
work, target a general to scientific audience:
■
Explain important concepts using analogies that less expert readers will
understand.
■
Define acronyms and terms that some readers will be unfamiliar with.
■
Use graphics to illustrate ideas or share preliminary results.
In the Experimental Approach section, shift to a more expert audience (e.g.,
PhD-level chemists):
■
Demonstrate your expertise and ability to do the proposed work.
■
Use acronyms as you would in a journal article.
By following this two-tiered approach, a less expert reviewer will be able to follow
the main ideas of your work, whereas an expert reviewer will be able to judge the
intellectual merit of your proposal fully.
Another aspect of audience is readability. Although your science must be topnotch (complete with sophisticated terminology), your proposal must also be
highly readable. This apparent conflict can be resolved by using an accessible
writing style: keep sentences short, use bulleted lists and other easy-to-read formats, and include graphics to break up the text. Reiterating themes and “telling
Overview of the Research Proposal
375
a story” throughout your proposal (as we emphasize in chapters 12–14) will
also increase your proposal’s readability. As a rule of thumb, a 15-page proposal
should take about an hour to read (less time than it typically takes to read a fivepage journal article). If your proposal is too difficult to read in this time frame, it
may be written for the wrong audience.
Exercise 11.13
Refer back to the RFPs that you found for exercise 11.11, or select another RFP.
Read the RFP for information about audience. What hints are offered about audience? In your own words, describe the target audience to authors who will be
writing this proposal.
Organizing the Proposal
In this section, we describe the organizational structure modeled in this textbook for the research proposal. In truth, there is no one “right” structure for a
proposal. Unlike journal articles, which conventionally follow the IMRD format
(see chapter 2), no consensus structure exists for proposals. They are all a bit different, each requiring a slightly different organizational approach. Thus, we have
developed a generic organizational structure, one that captures the essence of
many proposals but is not specific to any single proposal. We leave it up to you to
adapt this structure to meet the needs of your specific proposal.
If you are lucky, your RFP will offer organizational guidelines. If it does, by
all means, follow them, to the point of mirroring the suggested headings and
subheadings in your proposal. This will help reviewers locate pertinent information in your proposal and will improve your proposal’s readability (and rating).
If, however, your RFP does not provide such guidance, or you are writing a fictitious proposal to improve your writing skills, our generic structure will get you
started. Below we outline the generic proposal structure used in this textbook,
including (1) proposal headings, (2) major divisions of the proposal, and (3) main
sections of the Project Description (the primary major division of the proposal).
This information can serve as a roadmap to guide you through chapters 12–14.
Proposal Headings
Because the organizational structure of most research proposals is complex,
headings of different hierarchical levels (level 1, level 2, level 3, etc.) are needed
to help clarify the structure. Two commonly used styles are illustrated in generic
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The Research Proposal
Table 11.2 Generic forms of two heading styles (levels 1–3) commonly used in research
proposals.
Style 1
MAJOR DIVISION TITLE
Style 2
MAJOR DIVISION TITLE
LEVEL 1 HEADING
I. LEVEL 1 HEADING
Level 2 Heading
(A) Level 2 Heading
Level 3 Heading. Text . . .
(1) Level 3 Heading. Text . . .
form in table 11.2. (Style 1 is illustrated again in table 11.3, with actual headings.)
The only difference between the two styles is that style 2 includes numbers and/
or letters to signal level changes, and style 1 does not. In both styles, major section titles are bolded, centered, and written in all capital letters. Level 1 and level
2 headings differ in their use of capitalization, but both styles are bolded and
left-justified and are given a line of their own. Level 3 headings are bolded and
indented one tab position and conclude with a bolded period. For level 3 headings, the text begins after the period, on the same line as the heading. Authors
are free to choose their own style, as long as they use it consistently throughout
the proposal.
Major Divisions of the Research Proposal
Research proposals typically comprise three major divisions. Each division is
demarked with its own title (table 11.2). These titles differ from other headings in
the proposal because they are centered rather than left-justified. The three division titles used in this textbook (and in most proposals) are
PROJECT SUMMARY
PROJECT DESCRIPTION
REFERENCES CITED
The Project Summary is a one-page document, suitable for publication, that offers
a self-contained description of the proposed research activities (see chapter 15).
The References Cited section includes a complete listing of all sources cited in
the proposal and is typically not page restricted (see chapter 17 for directions
on formatting citations and references). The Project Description is the heart
of the research proposal. It is page restricted (usually 4–30 pages, depending on
the proposal) and is divided into sections and subsections, each with its own
heading. The Project Description is the focus of chapters 12–14.
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377
Table 11.3 The three main sections of the Project Description addressed in this textbook, with
suggested headings for the moves in each section (level 1–3 headings in style 1).
Section
Moves
Suggested Headings
Goals and
Importance
(chapter 12)
1. State goals and objectives
GOALS AND OBJECTIVES
1
2. Establish importance
PROJECT SIGNIFICANCE
1
EXPERIMENTAL APPROACH
1
1. Share prior accomplishments
Prior Accomplishments
2
2. Share preliminary results
Preliminary Results
2
3. Describe proposed methodology
Proposed Methods
2
Objective 1.
3
Objective 2.
3
1. Present a project timeline
PROJECT TIMELINE
1
2. List expected outcomes
EXPECTED OUTCOMES
1
3. Conclude the proposed work
CONCLUSIONS
1
Experimental
Approach
(chapter 13)
Outcomes
and Impacts
(chapter 14)
Level
3. Introduce proposed work
Main Sections of the Project Description
The Project Description is typically divided into three main sections (table 11.3).
The first main section introduces project goals and importance (chapter 12). The
second section describes the experimental approach (chapter 13). The third section summarizes project outcomes and impacts (chapter 14). Each main section
(and corresponding chapter) is organized by moves. The major moves are listed
in table 11.3, along with headings that authors commonly use in their proposals
to signal these moves. (Note: For instructional purposes, we have reformatted the
headings in proposal excerpts included in this module to conform to style 1, as
depicted in table 11.3.)
Examining Sample RFPs
We conclude this chapter with two sample RFPs. Excerpt 11B is a generic RFP
created for instructional purposes, to aid readers who have not yet found a suitable RFP and funding agency. The generic RFP, although highly abbreviated, captures the essence of many RFPs and can be used to guide your writing as you
prepare or revise a research proposal.
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The Research Proposal
Excerpt 11C is from the RFP for the NSF Faculty Early Career Development
Award in Chemistry (CAREER), a prestigious award offered by the NSF to exceptional junior faculty. In the rest of this module, we use excerpts from successful CAREER proposals to illustrate effective proposal-writing techniques and
to apply the read-analyze-write approach to writing; hence, it is important that
you review the RFP that motivated these proposals. (Note: CAREER proposals
require authors to describe, in what the NSF calls a Career-Development Plan,
both research and educational activities. In this textbook, we focus almost exclusively on the research activities proposed by the CAREER authors.)
Exercise 11.14
Read through the generic RFP in excerpt 11B and answer the following questions:
a. What are the three major divisions of the generic RFP?
b. Consider the information requested in the Project Description. What headings might you use to signal the requested information? Suggest a list of
headings for the Project Description using style 1 or 2. (Consult tables 11.2
and 11.3 as needed.)
c. Give examples of instructions that are quite specific.
d. What audience is identified?
e. What, if anything, appears to be missing from this generic RFP?
Excerpt 11B (an abbreviated, generic RFP that models essential features of scientific
research RFPs)
Project Summary. In one page or less, write a summary, suitable for publication,
of proposed activities. It should not be an abstract of the proposal but rather a selfcontained description of the proposed work. The summary should be written in the
third person and include descriptions of (1) the goals and objectives of the project, (2)
the importance of the project, (3) the proposed methods, and (4) the broader impacts of
the work. It should be written for a scientifically literate reader, but not necessarily an
individual in your field or discipline.
Project Description. The Project Description may not exceed 5 pages (Times New
Roman 12-pt font, 1.5 line spacing, numbered from page 1 to 5). Tables, figures, and
all graphics must be included within the 5-page limit. The Project Description should
include a title and address the following:
■
a clear statement of the project goals and objectives
■
the importance and significance of the proposed work
■
essential background information, relating the proposed work to current knowledge
in the field
Overview of the Research Proposal
379
■
a clear description of the experimental methods
■
preliminary results, when appropriate
■
a timeline or work plan
■
projected outcomes
■
broader impacts of the work
References Cited. Begin References Cited on a new page (Times New Roman 12-pt
font, 1.5 line spacing). There is no page limit for this section, but we encourage you to
limit references to those that have most greatly influenced your work. Format your references appropriately (numerical or alphabetical), paralleling the format used for in-line
citations. Include full journal article titles and all authors listed in the order in which
they appear in the journal article.
Exercise 11.15
Read excerpt 11C and answer the following questions:
a. What are three major divisions of the CAREER proposal?
b. The Project Description is divided into two sections. What is each section
called? Suggest a purpose for each section.
c. Based on the information presented in the CAREER RFP, suggest headings
that could be used to organize the Career-Development Plan.
d. Assign each proposed heading from (c) to one of the following sections of the
Project Description used in this textbook: goals and importance, experimental approach, or outcomes and impacts. (Consult table 11.3.)
Excerpt 11C (adapted from NSF Program Solicitation: Faculty Early Career Development
(CAREER) Program. Proposals for Fiscal Years 2003, 2004, and 2005. http://www.nsf.gov/
pubs/2002/nsf02111/nsf02111.htm (accessed January 3, 2008))
Project Summary: See GPG Section II.C.1.
Summarize the integrated research and education activities of the proposed careerdevelopment plan.
Project Description: See GPG Section II.C.3.
Note: the project description may not exceed 15 pages.
a. Results from Prior NSF Support, if applicable.
b. Career-Development Plan. Provide a well-argued and specific proposal for activities that will, over a 5-year period, build a fi rm foundation for a lifetime of integrated
contributions to research and education. (For examples of possible activities, refer to
CAREER Program Description in Section II.A. and the document “NSF Merit Review
Broader Impacts Criterion: Representative Activities,” located on the NSF Web site at
http://www.nsf.gov/pubs/2002/nsf022/bicexamples.pdf.)
380
The Research Proposal
The plan should be developed in consultation with the department head or
equivalent organizational official and include
■
■
■
■
■
The objectives and significance of the proposed integrated research and education
activities;
The relationship of the research to the current state of knowledge in the field, and
of the education activities to the current state of knowledge on effective teaching
and learning in one’s field of study;
An outline of the plan of work, describing the methods and procedures to be
used, including evaluation of the education activities. Both research and education activities should be included in the plan for each year, but the relative
amount of effort devoted to each may vary from year to year;
The relation of the plan to the PI’s career goals and job responsibilities, and to the
goals of his/her department/organization; and
A summary of prior research and educational accomplishments.
References Cited: See GPG Section II.C.4.
11A Writing on Your Own: Identify a Proposal Topic and RFP
Identify a topic for your research proposal. Find a funding agency that might support your
topic. (Hint: Look at the Acknowledgments sections of journal articles in your research
area. What funding agencies have been acknowledged by the authors?) If you cannot find
a suitable funding agency, assume that you are seeking an internal award through your
home institution.
Find an RFP that you can follow to write your proposal (ideally, one from the funding
agency that you selected). If you cannot find a suitable RFP, use the generic RFP in
excerpt 11B.
Jot down at least five reasons why your topic is important. How might society benefit
from your proposed work?
Chapter Review
To check what you’ve learned in this chapter, define each of the following terms
and explain its importance, in the context of this chapter, to a chemistry colleague
who is new to the field:
applied research
external funding
principal investigator
broader impacts
fundamental research
RFA
co-principal investigator (co-PI)
internal funding
RFP
Overview of the Research Proposal
381
Also explain the following to a friend or colleague who hasn’t yet given much
thought to writing a research proposal:
■
Main purpose(s) of a research proposal
■
Difference(s) between a research proposal and a Project Description
■
Three tactics used to write a persuasive proposal
■
Three C’s of intellectual merit
■
Common reasons for the rejection of a research proposal
■
Three major sections of a research proposal
■
Three main sections of a Project Description
■
Challenges associated with defining an appropriate audience for a research
proposal
Additional Exercises
Exercise 11.16
Excerpt 11D, from the RFP for the NSF Collaborative Research in Chemistry
(CRC) Grant, begins with a description of the program, which identifies the
purpose of the grant and eligibility requirements. That description is followed
by Full Proposal Instructions, which provide step-by-step guidance for writing
three major divisions of the proposal: Project Summary, Project Description, and
References Cited. Read excerpt 11D and answer questions a–h.
(Note that the original RFP required six additional sections, not included in
excerpt 11D: Bibliographical Sketches, Budget, Current and Pending Support,
Facilities, Supplementary Documentation, and Suggested Reviewers. These sections are beyond the scope of this textbook.)
a. Describe how the RFP addresses the three essential features of a proposal:
need, intellectual merit, and broader impacts.
b. What three sections are required in the Project Description? How many
pages should each section contain?
c. Create a list of headings that you might use if you were writing this proposal.
d. The RFP lists eight items (labeled a–h) to be addressed. Which of these items
are common to many proposals? Which items seem to be specific to this
proposal?
e. The RFP makes reference to the Grant Proposal Guide (GPG). Locate the
guide on the NSF Web site (www.nsf.gov) by searching for GPG. Browse
through the guide and comment on the types of information that it
contains.
382
The Research Proposal
f. Like most proposals, this RFP requests a Project Summary. What should be
included in the summary? How long should it be?
g. What format should the author(s) use in preparing references?
h. What audience should the authors address in the proposal?
Excerpt 11D (sample RFP adapted from NSF Collaborative Research in Chemistry (CRC):
Program solicitation, NSF 03–583. http://www.nsf.gov/pubs/2003/nsf03583/nsf03583.htm
(accessed January 3, 2008))
Program Description
The CRC Program enables researchers from diverse scientific and engineering backgrounds to respond to recognized scientific needs, to take advantage of current scientific opportunities, or to prepare the groundwork for anticipated significant scientific
developments in chemistry. CRC proposals will involve three or more investigators with
complementary expertise. The members of the collaborative team can come from more
than one institution and can include non-academic and international scientists. The
principal investigator will most likely be a chemist; however, there is no restriction on
the scope of disciplines represented by the co-investigators. Investigators may include,
in addition to chemists, researchers from other science and engineering disciplines
appropriate to the proposed research.
The use of cyber-infrastructure to enable and enhance collaborations is encouraged.
Full Proposal Instructions
Proposers are strongly encouraged to consult the proposal submission checklist included
in the Grant Proposal Guide as they prepare their proposal. Proposals not compliant
with the proposal preparation guidelines, as supplemented by the following instructions,
may be returned without review.
Project Summary. One-page limit, including the names and affiliations of all senior
personnel. The project summary must address both the intellectual merit and broader
impacts of the proposed CRC project.
Project Description. A total of twenty (20) pages, including Results from Prior
Support, Modes of Collaboration and Education, and Management Plan. CRC proposals
are likely to be read by non-specialists at some stage of the review process. It is, therefore, particularly important that they be written to emphasize the impact of the projects
on the chemical sciences in a broad context.
1. Research Plan. Narrative, not to exceed eighteen (18) pages, consisting of the following items:
a. An explanation of the scientific context, intellectual merit, relevance to chemistry
and timeliness of the proposed project.
b. A description of the proposed research.
c. A justification for why a collaborative effort involving at least three investigators is
necessary to carry out the proposed project.
Overview of the Research Proposal
383
d. A description of the contribution to be made by each senior investigator.
e. A discussion of the broader impacts of the proposed work.
f. A timeline for the planned work and a justification for the duration.
g. Plans for disseminating the results.
h. Results from prior NSF support.
2. Modes of Collaboration and Education [section omitted from excerpt]
3. Management Plan [section omitted from excerpt]
References Cited. References should include full titles of articles and book
chapters cited. This section includes bibliographic citations only and must not be
used to provide parenthetical information outside of the Project Description.
Please indicate with an asterisk (*) references co-authored by two or more proposal
investigators.
Cyber-infrastructure
Computers, technologies, wireless connections, and other information technology services
that enable and enhance collaboration within and between institutions.
Exercise 11.17
Excerpt 11E is from the National Cancer Institute’s Quick Guide for Grant
Applications. It is not an RFP but rather a tool for helping investigators prepare a
proposal. We include (1) parts of a section that outline the typical components of
a proposal and (2) parts of another section that describe the contents of a Project
Description (referred to as a “Research Plan”). Read over the excerpt and answer
these questions:
a. In what ways do these sections reinforce what has already been stated in this
chapter?
b. What differences do you notice?
c. Consider the four mandated sections of the Research Plan (A–D, itemized
under “General Proposal Outline”) and the five bulleted questions listed
under “Content”. In which sections of the Research Plan should each of the
questions be answered?
d. Look over the list of suggestions. Which heading style (style 1 or style 2) is
inferred? (Refer to tables 11.2 and 11.3, if needed.)
384
The Research Proposal
Excerpt 11E (adapted from the National Cancer Institute’s Quick Guide for Grant Applications.
http://deainfo.nci.nih.gov/extra/extdocs/gntapp.htm (accessed January 3, 2008))
General Proposal Outline
Abstract
Research Plan
A. Specific A ims
B. Background and Significance
C. Preliminary Results/Progress Report
D. Research Design and Methods
Research Plan (Overview)
Purpose: The purpose of the research plan is to describe the what, why, and how
of the proposal. This is the core of the proposal and will be reviewed with particular
care. . . . The assessment of this research plan will largely determine whether or not the
proposal is favorably recommended for funding.
Recommended Length: The maximum length of the research plan is 25 pages.
Content: The research plan should answer the following questions:
■
What do you intend to do?
■
Why is this worth doing? How is it innovative?
■
What has already been done in general, and what have other researchers done in
this field? Use appropriate references. What will this new work add to the field of
knowledge?
■
What have you (and your collaborators) done to establish the feasibility of what you
are proposing to do?
■
How will the research be accomplished? Who? What? When? Where? Why?
Suggestions
1. Make sure that all sections (A, B, C, and D—the what, why, and how of the proposal)
are internally consistent and that they dovetail with each other. Use a numbering
system, and make sections easy to find. Lead the reviewers through your research
plan. One person should revise and edit the fi nal draft.
2. Show knowledge of recent literature and explain how the proposed research will
further what is already known.
3. Emphasize how some combination of a novel hypothesis, important preliminary
data, a new experimental system, and/or a new experimental approach will enable
important progress to be made.
4. Establish credibility of the proposed principal investigator and the collaborating
researchers.
Overview of the Research Proposal
385
Exercise 11.18
Reflect on what you have learned about writing a research proposal thus far by
writing a thoughtful response to one of the following:
a. Reflect on the three persuasive tactics essential for funding (i.e., establishing
a need, demonstrating intellectual merit, and explaining broader impacts) in
relation to a research topic of interest to you.
■
■
■
How might you establish a need for your area of interest?
How will you demonstrate intellectual merit?
What are the broader impacts of the research area?
b. Reflect on the vital importance of research proposals in the lives of chemists.
■
■
■
What skills do you want to master to be able to write an effective research
proposal?
How will you go about mastering those skills?
What strengths and weaknesses do you bring to the process of writing a
research proposal at this point in your professional development?
c. Reflect on the interrelationships among creativity, credibility, and competence (the three C’s) when establishing intellectual merit in a research
proposal.
■
■
■
What strategies will you use to demonstrate your creativity in a research
proposal?
What have you done that will assist you in establishing your credibility in
a research proposal?
How will you emphasize your competence?
d. Reflect on the similarities and differences between a research proposal,
journal article, and/or scientific poster.
■
■
■
386
What are the major differences between/among these genres?
What are the similarities between/among these genres?
How do the similarities and differences influence the ways in which each
genre is written?
The Research Proposal
12
Writing the Goals and Importance Section
Good proposals stimulate my curiosity. As I read a proposal,
I begin to think up new questions about the project and its
science. The best proposals answer those questions before I’m
done reading. I have a lot of respect for writers who can anticipate
the questions that a reader will have and provide answers.
—Alexander Grushow, Rider University
This chapter focuses on writing the first section of the Project Description. The
central purposes of this section are to identify project goals and objectives,
highlight the importance of the research, provide relevant background information, and introduce the proposed research. By the end of this chapter, you
should be able to do the following:
■
Distinguish between broad goals and specific objectives
■
Format a list of objectives correctly
■
Emphasize the importance of your research
■
Affirm your intellectual merit
■
Know when and how to introduce your proposed work
■
Select appropriate headings
Staying on Track
This chapter covers what normally is presented in the first major section of the Project
Description.
Common level 1 headings in this section are
GOALS AND OBJECTIVES
PROJECT SIGNIFICANCE
As you work through the chapter, you will write the opening section of your
Project Description. The Writing on Your Own tasks throughout the chapter
guide you step by step as you do the following:
12A Prepare to write
12B Create a list of project goals and objectives
12C Introduce and develop the research story
12D Introduce your proposed work
12E Complete the opening section
Reading and Analyzing Writing
We begin with excerpt 12A for you to read and analyze on your own. The excerpt
contains only parts of the author’s original Goals and Importance section. Her
full section starts with a statement of goals and significance, which is followed by
individual descriptions of three separate but related studies. In excerpt 12A, we
include only (1) the statement of goals and significance and (2) the description of
the second study.
Exercise 12.1
Read and analyze excerpt 12A and answer the following questions:
a. In the first paragraph, the author introduces the research area and its significance. Restate the area and its significance in your own words.
b. In the second paragraph, the author describes the principal goal of the
research. Restate this goal in your own words.
c. In Study 2, the author describes specific objectives of her project. State two of
them in your own words.
d. How does Study 2 link back to the goals and significance stressed in the
opening section of the proposal?
e. The author cites five works in Study 2. How do the citations strengthen her
proposal?
Excerpt 12A (from Aga, 2002)
PROJECT DESCRIPTION
GOALS AND SIGNIFICANCE OF PROPOSED WORK
The increased use of agricultural chemicals such as herbicides and animal antibiotics
has been mirrored by an increased public concern regarding the impact of xenobiotic
388
The Research Proposal
compounds on the environment and human health. The pressure to provide new information on the fate of pesticides in the environment has become a monumental task for
government and industry. In addition to pesticides, antibiotics are now being recognized
as emerging contaminants because of their high potential to enter surface and ground
waters from animal confi nement operations and manure-treated agricultural fields. The
widespread use of antibiotics in animal production is an important issue that has currently attracted attention due to the increased incidence of antimicrobial resistance in
food-borne microorganisms. Knowledge of the mechanism for degradation and transport of environmental contaminants is essential in developing guidelines for effective
water-quality management actions.
The principal goal of the PI’s planned research activities is to develop innovative
analytical methods, such as immunochemical techniques, and apply these methods in
environmental investigations. Emphasis is placed on the development of immunochemical methods because of their cost effectiveness and general applicability in conducting
environmental investigations. In addition, there is an increased interest from the regulatory agencies to develop analytical methods that are fast and field-portable for on-site
monitoring; these are characteristics of immunochemical methods. There are three
closely related studies described in this proposal, all of which involve analytical methods
development and have applications to studies that examine the fate and behavior of
important agricultural contaminants in the environment.
STUDY 1: [not included]
STUDY 2: STEREOSELECTIVITY OF METOLACHLOR DEGRADATION IN SOIL
Objectives and Significance
This study will provide fundamental information on the effect of stereoisomerism
on the environmental fate of a widely used chloroacetanilide herbicide, metolachlor.
Metolachlor is classified as a potential carcinogen and is the second most extensively
used herbicide in the United States (7). Biological dechlorination of metolachlor leads
to the formation of more polar metabolites (8), metolachlor oxanilic acid (OXA), and
metolachlor ethanesulfonic acid (ESA) (Figure 3). Metolachlor OXA and metolachlor
ESA are found at higher concentrations and are more frequently detected in surface and
ground water than their parent compound (9).
Metolachlor is applied as a mixture of eight different stereoisomers, only four of
which have herbicidal activity (10). This implies that the other four isomers are applied
as contaminants, with no additional benefit to crop production. Whether the chirality
of metolachlor influences its degradation rate is unknown. This lack of information is
mainly due to the difficulty of separation and analysis of its isomers. Because the stereochemistry of compounds plays an important role in their biological activity and degradation pathways, it is valuable to investigate the influence of stereochemistry on the rate of
metolachlor degradation in soil.
Analytical methods to separate and quantify individual isomers of metolachlor and
its metabolites are imperative to accomplish this investigation. Chromatographic separation of metolachlor and its metabolites is complicated due to the existence of several
rotational isomers for each compound. Thus, these compounds will be fractionated
Writing the Goals and Importance Section
389
by solid-phase extraction (SPE) into metolachlor (neutral fraction), metolachlor OXA
(carboxylic fraction), and metolachlor ESA (sulfonic acid fraction). Newly developed
stereoselective immunoassays (specific only to the herbicidally active S-isomers) and
chiral chromatographic techniques will be employed to achieve quantification of individual isomers. These methods will be used to measure the enantiomeric ratios (ER)
of metolachlor and its metabolites in pesticide-treated soil samples. Also, the rate of
disappearance of metolachlor versus the rate of formation of metabolites will be followed
under controlled conditions.
Pesticide enantiomers are useful as tracers of the soil and water-air exchange process
for the following reasons. Although a few chiral pesticides are manufactured as singleenantiomer products, most are racemic mixtures having a 1:1 enantiomeric ratio.
Enantiomers have the same physical and chemical properties. As a result, transport
processes (leaching, volatilization, and atmospheric deposition) and abiotic reactions
(hydrolysis and photolysis) do not discriminate between the enantiomers, leaving ERs
unaffected. In contrast, metabolism of pesticides by microorganisms in water and soil
and by enzymes in higher organisms often precedes stereoselectively, leading to nonracemic residues and alteration of the original ER (11). By examining ERs, it is possible
to differentiate the relative importance of biological and physical processes in pesticide
degradation. This information will have important consequences on water treatment and
pesticide application management.
Information on the possible stereoselectivity of metolachlor degradation will prove
useful in understanding degradation pathways and in identifying components in natural
environments that shorten or enhance herbicide half-life. In addition, should the degradation of metolachlor be found stereoselective, it will be important for the manufacturers to consider production of the pure isomeric forms of this herbicide and the other
chloroacetanilides (e.g., alachlor and acetochlor) to minimize pollution. Lastly, regulatory agencies may also need to re-examine the water-quality standards set for chloroacetanilide herbicides taking into consideration the differences in degradation rates of the
stereoisomers, if there are any.
STUDY 3: [not included]
Principle vs. Principal
Principle (noun): a basic truth
Principal (adj.): main; chief
(See appendix A.)
Capitalization
Chemical names are not capitalized unless they are at the start of a sentence. (See
appendix A and also table 3.1.)
390
The Research Proposal
Exercise 12.2
In anticipation of the moves for this section (described below), find one sentence
in excerpt 12A that accomplishes each of the following tasks:
a. Identifies a specific project objective
b. Emphasizes the importance of the research area
c. States a fundamental concept
d. Provides relevant background information
e. Identifies a gap in the field
12A Writing on Your Own: Prepare To Write
After selecting a topic for your research proposal (refer back to the Writing on Your
Own task in chapter 11), you are ready to begin your review of the literature. Find and
read at least four papers in your research area. As you identify papers that you are
likely to cite in your proposal, begin compiling your References Cited section. (See
chapter 17.)
Take notes as you read, jotting down key ideas from each paper. State why each work is
important. Organize what you have learned from these papers in your own way. Think of
approaches for sharing this knowledge and its importance with your readers.
Jot down ideas about why your research area is important. Think of at least three
ideas on your own, and then augment your list with ideas suggested in the literature. Is
it a growing area of interest? What benefit(s) or new knowledge will your research area
provide? (Search for these ideas in the Introduction and Conclusions sections of journal
articles.)
Analyzing Organization
A typical move structure for the opening section of the Project Description is
presented in figure 12.1. (Of course, if your Request for Proposals recommends a
different organizational structure, use that one instead.) Collectively, these moves
and submoves depict conventional steps taken by writers to share the goals and
objectives of the research, establish its importance, provide relevant background
information, and introduce the proposed work. Citations to others’ works are
common in these moves, particularly in the second move, which has the purpose
of placing the proposed work within the context of current knowledge in the
field. Because move 1 states specific goals and objectives, it has a more narrow
focus than moves 2 and 3.
Writing the Goals and Importance Section
391
1. State Goals and Objectives
2. Establish Importance
2.1 Identify the research area
2.2 Develop the research story
Explain
fundamental
concepts
Provide essential
background
information
Cite
relevant
literature
3. Introduce the Proposed Work
3.1 Identify gap(s) in the field
3.2 Introduce your project to fill the gap(s)
Figure 12.1 A visual representation of the suggested move structure for a Goals and
Importance section of the Project Description.
With figure 12.1 in mind, we are ready to analyze how authors accomplish
these moves in authentic proposals. Moves 1–3 are examined below. Headings
for each move are suggested, and an analysis of writing features for each move is
provided.
Exercise 12.3
Reread the first two paragraphs of excerpt 12A and answer the following
questions:
a. What moves are present?
b. Does the author follow the move structure presented in figure 12.1? If not,
why might there be differences?
Move 1: State Goals and Objectives
Many, but not all, Project Descriptions begin with a short overview of project
goals and objectives. Some Requests for Proposals (RFPs) require this explicitly,
but many Project Descriptions start this way even if not required (e.g., 16 of the
22 CAREER proposals cited in this textbook begin by stating the goals and objectives of the proposed work). The purpose of this move is to highlight expected
392
The Research Proposal
Table 12.1 Common level 1 headings for move 1 of the Goals and Importance section.
GOALS AND OBJECTIVES
SPECIFIC AIMS
GOALS AND SIGNIFICANCE
RESEARCH OBJECTIVES
accomplishments of the proposed work, allowing reviewers to quickly judge if the
proposal is in line with funding objectives. The move stands apart from the rest of
the proposal and is typically not viewed as the true start of the Project Description.
The move is commonly signaled with a level 1 heading (see tables 11.2 and 11.3).
We caution against using a colon after the heading:
Not recommended GOALS AND OBJECTIVES:
Recommended
GOALS AND OBJECTIVES
Whatever heading style you choose, be sure to use the same style for equivalent headings throughout your proposal. A few common headings for move 1 are
shown in table 12.1.
Goals vs. Objectives
In this textbook, we use the term goals to refer to broader purposes and the term objectives
to refer to the specific steps taken to reach a goal.
Occasionally, you will find the definitions for the two terms reversed.
What is most important is consistency. Avoid using the terms interchangeably within a
single document.
Analyzing Excerpts
One’s research funding is dependent on clear thinking and the expression
of ideas in a coherent manner. In other words, you have to convince
readers that you know what you are talking about and that you will be
able to meet your established goals.
—Richard Malkin, University of California–Berkeley
Let’s examine this move in authentic proposals. In most proposals, the first sentence, immediately after the major division title (e.g., Project Description), states
the overall goal of the proposed research (e.g., “The goal of this proposed research
is to . . . ”). Words like long-term, overarching, ultimate, or overall often precede the
word goal, to denote that the goal is broad in scope and may take several years
Writing the Goals and Importance Section
393
(and several grants) to accomplish. Most proposals include only one or two goals,
in large part because more than two may be viewed as unrealistic for a single
proposal. A few examples are shown in P1–P4; each is the opening sentence of the
author’s Project Description. Note that these goals, although broad in scope, are
also rich in scientific content and often target an expert audience:
P1 The goal of the proposed research is the development of new
stereoselective [3 2] cycloaddition reactions based on Lewis-acid
promoted ylide formation for the preparation of complex organic
heterocycles (eq 1). (From Johnson, 2003)
P2 The long-term goal of the proposed research is to create functional model
complexes of metalloprotein active sites. (From Houser, 2001)
P3 The goal of the proposed research is to investigate the structural and
dynamic properties of integral membrane proteins through the use of
EPR spin-label spectroscopy and solid-state NMR spectroscopy. (From
Lorigan, 2002)
P4 The ultimate goal of the proposed research is the identification and
development of fluorescent chemosensors for heavy metal ions and small
organic molecules in water. (From Finney, 1999)
The goal statement is followed by specific objectives, which spell out the steps
needed to accomplish the larger goal. Ideally, these objectives should pass the
SAM test: they should be specific (specifying what you will do and how you will
do it), achievable (within a realistic time frame), and measurable (implying ways
that you will measure success). Because of their specificity, objectives are usually
written for an expert audience. (Paul, A. The Grant Institute’s Grants 101, personal communication, 2006)
The SAM Test
Effective objectives should pass the SAM test by being
Specific
Achievable
Measurable
Examples of goal statements and specific objectives are shown in excerpts
12B–12E. The first two examples (excerpts 12B and 12C) enumerate objectives;
excerpt 12B lists the objectives in continuous text, while excerpt 12C presents
objectives in a displayed list. The latter approach is easier to read and preferred
if space permits. (For another example of a list, refer to the list of nine objectives
in excerpt 11A.) Note that each excerpt includes a heading, a general goal, and a
list of objectives.
394
The Research Proposal
Lists in Research Proposals
Lists are common in research proposals. They are used to delineate project objectives
(chapter 12) and expected outcomes (chapter 14).
Lists are not common in journal articles; hence, this is an important style difference
between the two genres.
Excerpt 12B (from Lyon, 2000)
SPECIFIC AIMS
The goal of this research is to develop a new class of bioresponsive materials that
undergo rapid, large-magnitude, volume-phase transitions in response to specific biological stimuli. Our approach to these materials is based on two fundamental aspects of
hydrogels: (1) hydrogel solvation/desolvation thermodynamics can be perturbed . . . and
(2) hydrogel chemistry can be reduced. . . . Accordingly, this research will involve the
following specific objectives: (1) the synthesis of polymer-protein bioconjugates, (2) the
fabrication of nano-sized hydrogel thin films, (3) the development of synthetic models
for particle size control, and (4) the design and synthesis of new core-shell hydrogel
particles. By completely characterizing the resultant materials with respect to their
structure, morphology, thermodynamics, and kinetics, we can obtain a fundamental
understanding of the hydrogel structure-function relationship. In turn, this will allow us
to develop rational designs for truly bioresponsive devices.
Commas
Commas are used to separate items in a list of three or more items. Include a comma
before the “and” preceding the last item. (See appendix A.)
Excerpt 12C (from Patrick, 2000)
RESEARCH OBJECTIVES
The overall goal of this research is to explore the use of thermotropic liquid crystal
(LC) solvents as new and versatile media for the engineered growth of molecular thin
films. This goal will be pursued in two parts. First, a set of experiments is planned to
investigate fundamental aspects of thin film growth in LC media. These experiments
will help elucidate important physical phenomena and deepen our understanding of the
role played by the LC solvent. A second group of experiments will build on this foundation to prepare model thin film materials from several different molecular building
blocks. The specific research objectives are
1. to determine the influence of LC surface anchoring and bulk fluid curvature elasticity on orientational order in thin fi lms deposited from LC solvents. This will be
Writing the Goals and Importance Section
395
accomplished through two sets of experiments separately measuring the contribution
of each effect.
2. to develop a model that explicitly articulates the roles of these factors.
3. to apply this knowledge toward the preparation of two thin film systems:
a. bi-component composite films in which the alignment of one component is
unidirectional, and the alignment of the second component is random,
b. oriented molecular fi lms for use as re-writable anchoring layers.
Abbreviations
Most abbreviations (or acronyms) are defined at first use and then used without definition.
Abbreviations often omit periods (e.g., LC not L.C.). (See appendix A.)
Parallelism in Lists
See appendix A.
Exercise 12.4
Reread passages P1–P4 and excerpts 12A–12C, and answer the following
questions:
a. Who is the intended audience for move 1?
b. How are the words “goal” and “objectives” used in move 1?
c. What verb tense(s) is used in move 1 (past, present, future)?
d. When should you use a colon (:) in an enumerated list?
e. When numbers are used to enumerate objectives, are they Roman (i, ii,
iii,. . . . ) or Arabic (1, 2, 3, . . . )? How are the numbers formatted?
f. Why do you think Aga (12A) and Lyon (12B) include their lists in continuous
text rather than in actual list form, as in excerpt 12C?
g. How well do the objectives in 12B and 12C meet the SAM test? Explain.
Excerpt 12D illustrates a slight variation of move 1. Rather than state project goals and objectives explicitly, the author frames them as research questions, again in list form. (Such an approach underscores the inquisitive nature
of science.)
396
The Research Proposal
Excerpt 12D (from Rose-Petruck, 2000)
SCIENTIFIC GOALS OF THE PROPOSED STUDIES
The following questions will be addressed in the proposed studies:
1. How exactly does the solvent modify the ligand motions during the first few hundreds of femtoseconds?
2. Does the ultrafast dissociation process of Fe(CO)5 in solution, and that of related
compounds in general, occur in a concerted or a rapid sequential way?
3. Which vibrational modes of the iron pentacarbonyl interact most strongly with the
solvation shells, and which vibrational modes lead to the eventual escape of only a
single carbonyl ligand?
4. If the dissociation process occurs in a concerted way causing instantaneous loss of
four CO-ligands, which ligand motions does the caging solvation shell inhibit?
5. The ultrafast laser pulse excites many vibrational modes of the metal carbonyl simultaneously (i.e., the vibrational modes are phase-coupled). Are the subsequent ligand
motions coherent or do ultrafast dephasing processes hinder coherent motions?
Colons (:)
A colon may be used to introduce a list of items, provided that the colon follows a complete sentence. (See appendix A.)
Exercise 12.5
Rephrase the questions in excerpt 12D as statements of objectives. Which
approach do you prefer? Why?
If you have only a few objectives, your proposal may read more smoothly if you
use ordinal language (e.g., first and second), as illustrated in excerpt 12E, rather
than a numbered list (as in excerpt 12D). Alternatively, you may leave out enumeration entirely. For example, in excerpt 12A, Aga describes her principal goal
(to develop innovative analytical methods for environmental applications) and
objectives (to develop immunochemical methods that are cost-effective, fast, and
field-portable and use them to monitor the fate of agricultural contaminants)
without any enumeration.
Excerpt 12E (from Lee, 2001)
SIGNIFICANCE AND OBJECTIVES
The overall goal of the proposed work is to broaden our understanding of nucleotide
chemistry through gas-phase mass spectrometric and theoretical quantum mechanical
studies. The objectives are twofold. First, the gas-phase acidity and nucleophilicity of
Writing the Goals and Importance Section
397
different sites on nucleobases will be explored to understand their fundamental electronic reactivity. Second, the chemistry of orotic acid will be examined to elucidate the
mechanism of conversion of this important nucleic biosynthetic precursor to uracil. The
significance of each facet of this program is outlined separately below.
First,
Ordinal language may be used in proposals. Use a comma after ordinal terms and other
introductory linking words and phrases, e.g.,
First, . . .
Second, . . .
. . . ; and third, . . .
However,
In contrast, . . .
(See appendix A and table 6.6.)
Exercise 12.6
Let’s assume that Lee (excerpt 12E) had said “Two research questions are
addressed” instead of “The objectives are twofold.” Rewrite the objectives as two
research questions.
Exercise 12.7
What headings are used in excerpts 12A–12E to identify move 1? Add new ones
to the list of common headings in table 12.1.
Beginning writers often choose words for their goals and objectives that either
are too nonspecific or overstate their case. For example, a novice writer might say
“We will see if this is the case” or “We will discover important new compounds.”
Although both sentences are grammatically correct, the fi rst is too nonspecific
(what exactly does the writer mean by the word see?) and the second is overstated (what if new compounds are not discovered?). Another common mistake
is to overuse the word experiment. The word experiment usually connotes a single
event (e.g., “In today’s experiment, we will synthesize cyclohexane.”). Research
involves countless experiments, which can span months or years; hence, scientists prefer words such as work, project, or study. These and other words and
398
The Research Proposal
Table 12.2 Words and phrases to avoid and their more appropriate alternatives.
Avoid words and phrases that
Instead, use words and phrases that
are informal and nonscientific, e.g.,
“We will (see, find out, look into, try to
figure out if) . . . ”
are more formal and scientific, e.g., “We
will (monitor, measure, determine, explore,
examine, investigate, analyze) . . . ”
overstate what may be achievable, e.g.,
“We will (discover, prove, create, cure,
find, put an end to) . . . ”
lead to measurable results, e.g., “We will
(develop, apply, measure, quantify, explore,
compile, examine, characterize, synthesize,
modify, adapt) . . . ”
promise success prematurely (before
the work has been done), e.g., “We
will (show, demonstrate, find, prove,
discover, create) that . . . ”
acknowledge assumptions or predictions,
e.g., “We (hypothesize, expect, predict)
that . . . ” “Preliminary results suggest . . . ”
refer to a long-term project as an
“experiment” or “lab”, e.g., “In this
experiment, we propose to . . . ”
convey the long-term nature of the work,
e.g., “In this project, we propose to . . . ”
“In this work, we propose to . . . ”
phrases to avoid are presented in table 12.2, along with their more appropriate
alternatives.
Formal Vocabulary
See appendix A.
Exercise 12.8
Consider the following sentences. Identify words that should be avoided and suggest more appropriate alternatives (see table 12.2).
a. In our experiment, we will show that polyurethane films can be successfully
attached to biosensors and used to detect nerve agents.
b. We will discover new types of sandwich compounds, composed of polycyclic
aromatic hydrocarbons surrounding a single metal atom.
c. The goal of our research is to see if we can find novel biomolecules that will
bind to hairpin and i-Motif DNA.
d. We will look at how injecting swine with artificial porcine somatotrophin
affects carcass mass and composition.
Writing the Goals and Importance Section
399
Analyzing Writing
Before we conclude our discussion of move 1, we call your attention to the pointers accompanying excerpts 12A–12E. These pointers, together with their corresponding excerpts, highlight correct usages of the following words, punctuation,
or other writing features:
■
principle or principal (excerpt 12A)
■
capitalization (excerpt 12A)
■
commas in a list of three or more items (excerpt 12B)
■
abbreviations and acronyms (excerpt 12C)
■
parallelism in enumerated lists (excerpt 12C)
■
colons before a list (excerpt 12D)
■
commas after introductory linking words or phrases (excerpt 12E)
To test your knowledge of some of these features, complete exercises 12.9–12.12.
Refer back to the excerpts and pointers as needed.
Exercise 12.9
We have intentionally removed commas from the following passage adapted from
Fairbrother (2000). Where are additional commas needed?
For example a polymer’s interfacial characteristics determine chemical and physical properties such as permeability, wettability, adhesion, friction, wear and
biocompatibility.1–3 However polymers frequently lack the optimum surface properties
for these applications.1,4 Consequently surface modification techniques have become
increasingly desirable in technological applications of polymers.5,6
Exercise 12.10
Select the appropriate words and correct the punctuation in the following
paragraph.
Our principal/principle objective is to investigate the long-term effects of these pollutants.
Our methods will include: (1) extraction, (2) concentration and (3) purification of liquid
and solid samples. In principal/principle, the liquid samples should be easier to extract.
Exercise 12.11
Which of the following sentences are punctuated correctly?
a. Our approach is based on: hydrogel thermodynamics and hydrogel chemistry.
400
The Research Proposal
b. Our approach is based on two properties: hydrogel thermodynamics and
hydrogel chemistry.
c. Our approach is based on hydrogel thermodynamics and hydrogel chemistry.
Exercise 12.12
Revise the last three items in this list so that they are parallel with the first two
items (adapted from Lyon, 2000).
This research will involve the following specific objectives:
a. investigation of hydrogel solvation/desolvation thermodynamics
b. synthesis of polymer-protein bioconjugates
c. we will fabricate hydrogel thin films
d. synthetic models will be developed
e. hydrogel particles will be designed
Lastly, we briefly consider verb tense and voice used in move 1. Goals and objectives are commonly stated in present and/or future tense. Both active and passive
voice may be used. Common tense and voice combinations are summarized in
table 12.3. Personal pronouns (e.g., we, my, our) should be avoided in the opening
goal statement but may be used elsewhere in move 1:
Opening goal statement
Inappropriate My research goal is to . . .
Appropriate The goal of the research is to . . .
Elsewhere
Appropriate Our approach is based on . . .
Appropriate We will gain a fundamental understanding . . .
Table 12.3 Common functions of different verb tense–voice combinations in move 1 of the
Goals and Importance section.
Function
Tense–Voice
Combination
Example
State project goals
and objectives
Present–active
The goal of the research is to identify . . .
Present–passive
A set of experiments is planned to . . .
Future–active
The research will address the following . . .
Future–passive
This goal will be pursued in two parts.
Writing the Goals and Importance Section
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12B Writing on Your Own: Create a List of Project Goals and Objectives
After a Research Proposal topic is selected (refer back to the Writing on Your Own task in
chapter 11), it is time to specify project goals and objectives. Consider questions such as
these to begin the brainstorming process:
1. What is the overarching goal of your proposed work?
2. What steps will you take to achieve that goal?
Prepare a list of goals and objectives for yourself initially, to guide you in organizing the rest
of your proposal. Depending on the RFP that you have chosen, you may want to include
the list of goals and objectives in your final proposal, too. Make sure that you use the words
goal and objective as specified in the RFP. Usually goals refer to broader purposes and objectives refer to specific steps taken to reach a goal. If the RFP uses the terms in reverse, you
should do so, too.
Move 2: Establish Importance
When I began writing grant proposals, I had very little success but did
not understand what I was doing wrong. At that time, I thought that luck
was a big factor and that I just hadn’t been lucky yet. So to increase my
odds, I sent out more proposals. Basically, this just led to an increased
number of rejections. After several years of seemingly fruitless effort, I
finally really asked myself, what am I doing wrong? Why are reviewers
not recommending my proposals for funding? That is when my thinking
began to change.
I started thinking about the proposal as a communication tool to
market my ideas. I no longer expect the reviewer to do a lot of work
to understand my ideas or recognize the significance of my proposal. I
assume it is my job to convince the reader that the problem I am working
on and the solution I have proposed are compelling and have high value.
I work to grab the reader’s attention immediately and then serve up a
well-organized, persuasive, and easily readable presentation of my ideas.
I provide convincing answers to any obvious questions about the proposed
approach so that doubt does not have a chance to take root in the reader’s
mind. In short, in proposal writing, I think of the reader as the customer,
and I work to provide the best service possible.
—Joan Curry, University of Arizona
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The Research Proposal
Table 12.4 Common level 1 headings for move 2 of the Goals and Importance section.
PROJECT SIGNIFICANCE
PROJECT RATIONALE
SIGNIFICANCE OF PROPOSED RESEARCH
PROJECT BACKGROUND
Move 2 represents the true beginning of the Project Description. It is here where
authors establish importance, the unifying theme of the move. Each submove
in move 2, in some way, contributes to this theme. Establishing importance is
crucial to a successful proposal. Projects that are trivial or inconsequential are
unlikely to be funded. It is not enough to say, “This project is important.” Rather,
you must offer compelling reasons why it is important.
Move 2 is also where the research story begins; fundamental concepts are
explained, and background information is shared. The research story begins by
highlighting what others have accomplished, thereby laying the groundwork for
the proposed work in move 3. Common headings for move 2 (table 12.4) incorporate such words as significance and background. The heading for move 2 is typically
a level 1 heading (parallel to the heading for move 1).
Analyzing Excerpts
To illustrate how authors progress through move 2 in their proposals, let’s examine some excerpts. The first submove of move 2 identifies the research area and,
whenever possible, also hints at why the research area is important. For example,
in the following passages (all first sentences of move 2), the broad research area is
identified and its importance is suggested. The proposed work is not mentioned.
This does not occur until move 3.
P5 Maximizing the world’s agricultural efficiency depends on controlling
unwanted pests—especially weeds. (From Vyvyan, 2001)
P6 Preparation of new materials by directed synthesis at molecular-length
scales is the object of much current research in materials science, surface
chemistry, and the emerging field of crystal engineering. (From Patrick,
2000)
P7 The increased use of agricultural chemicals such as herbicides and
animal antibiotics has been mirrored by an increased public concern
regarding the impact of xenobiotic compounds on the environment and
human health. (From Aga, 2002)
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P8 Thermal conrotatory 4 ring opening of aziridines and epoxides is a
well-recognized method of generating azomethine and carbonyl ylides.1
(From Johnson, 2003)
Subject–Verb Agreement
See appendix A.
Exercise 12.13
Identify each research area addressed in P5–P8. Based only on the authors’ words,
suggest why each research area is important.
Exercise 12.14
Consider the following sets of sentences adapted from two research proposals.
In each set, determine which sentence is the opening sentence of move 2. Use
the move structure in figure 12.1 to assign a move to the other sentence. (Note:
Citations have been removed to make this exercise more challenging.)
Set 1 (adapted from Kohen, 2002)
a. The overall goal of this project is to seek a better understanding of how
enzymes activate covalent bonds.
b. The role of protein fluctuations in enzyme rearrangement, reactant binding,
and product release is well established.
Set 2 (adapted from Hergenrother, 2002)
a. Research in my laboratory will utilize combinatorial chemistry and modern
high-throughput screening techniques in an effort to make fundamental
biological discoveries.
b. In the past decade, combinatorial chemistry has exploded onto the scene of
modern science.
After introducing the topic, the research story is developed (submove 2.2).
Submove 2.2 involves two steps (in any order): (1) explain fundamental concepts
and (2) provide essential background information. In many proposals, explanatory remarks are included to help reviewers more fully comprehend the proposed science (recall that not all reviewers will be experts in the author’s field).
Furthermore, explanatory remarks demonstrate the authors’ understanding of
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The Research Proposal
the proposed science. These remarks may occur anywhere in a proposal, but
they are particularly common in move 2. Let’s consider a few examples. In the
simplest case, an explanatory remark may be embedded within a single sentence,
as illustrated in P9–P11:
P9
Allelopathy, the chemical interaction between plants and
microorganisms, has been known for thousands of years. (From
Vyvyan, 2001)
P10 Gas hydrates are nonstoichiometric compounds consisting of hydrogenbonded water molecules in a cagelike structure, which traps smalldiameter gas molecules. (From Tuckerman, 1999)
P11 Nitrite reductases (NiRs)—enzymes found in several strains of
denitrifying bacteria—catalyze the one-electron reduction of nitrite
anion to nitric oxide. (From Houser, 2001)
Alternatively, some concepts may be described in more detail, approaching a
near textbook-like description. Colored illustrations may be used and textbooks may be cited, if they were used as resources for this information. For
example, Hergenrother includes an introduction to apoptosis in his proposal,
using both text and graphics. A short passage from his text is reproduced in
excerpt 12F, where he describes how either underactive or overactive apoptotic processes can lead to dire cellular consequences. Understanding apoptotic processes is important to his proposed work, which involves apoptotic
proteins.
Citing Textbooks?
Authors may cite textbooks (or other authoritative sources) that are used to prepare
explanatory remarks in a research proposal.
Textbooks are not usually cited in journal articles (see chapter 6).
Excerpt 12F (from Hergenrother, 2002)
Apoptosis, or programmed cell death, is an essential process that results in the
methodical destruction of unwanted or potentially harmful cells.7 The proper functioning of this pathway is critical for cellular growth and maintenance, and modulation
of apoptosis has dire cellular consequences.8 For example, a down regulation of the
apoptotic cascade can cause the uninhibited growth of tumor cells. In such cases, small
molecules that restore proper apoptosis have the potential as powerful chemotherapeutic agents.9 Conversely, in certain degenerative disorders, the apoptosis pathway is
overactive, resulting in premature cellular death. In these cases, inhibitors of apoptosis
are desired.
Writing the Goals and Importance Section
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Another example is presented in excerpt 12G, where the author describes, in near
textbook-like detail, the phenomenon of quantum-mechanical tunneling. A fullcolor illustration is included in the proposal (although the figure here is in black
and white), depicting the different tunneling behaviors of light (e.g., hydrogen) and
heavy isotopes (e.g., deuterium and tritium). Later on in the proposal (not included
here), the author goes on to describe how the kinetic isotope effect (KIE) can be
used as a probe for tunneling. The KIE is defined (“the ratio of the reaction rates of
two isotopes of the same element”), and a second full-color illustration is included
to depict both a semiclassical model of the KIE (without tunneling) and a quantummechanical model (with tunneling). The author includes this information because
hydrogen tunneling is integral to his proposed research.
Full-Color Illustrations
Proposals often include full-color graphics to elucidate important concepts. Color graphics
should also make sense in gray scale, in case reviewers print out a hard copy.
Excerpt 12G (from Kohen, 2002)
Quantum mechanical tunneling. Tunneling is the phenomenon by which a particle
transfers through a reaction barrier due to its wave-like property.30,37 Figure 1 graphically illustrates this for a carbon-hydrogen-carbon double-well system. . . . Hydrogen
is so light that there is a significant uncertainty in its location at a given energy (the
Heisenberg uncertainty principle). When it is close to the reaction’s barrier, there is some
probability of finding it on the product side, if the barrier is narrow enough and the
reactant and product energy levels are degenerate. As illustrated in Figure 1, the lighter
isotope has a higher tunneling probability than the heavier one, suggesting that kinetic
isotope effects (KIEs) should be effective tools in studying tunneling.
E
light
isotope
heavy
isotope
R.C.
R
P
Figure 1. An example of ground state nuclear tunneling
along the reaction coordinate (R.C.). The reactant well
(R) is on the left side and the product well (P) is on
the right. The blue and red lines describe a light and
a heavy isotope probability function, respectively.
The greater the overlap of the R and P probability
functions, the higher the tunneling probability.
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The Research Proposal
Formatting Figures, Tables, and Schemes
See chapter 16.
Exercise 12.15
Select a topic that you are currently studying in research or coursework. First,
write a single sentence that includes an explanatory remark about the topic. Next,
write a paragraph that describes the topic in more detail, with an illustration if
possible. Include citations, as appropriate, in the paragraph.
Another step in developing the research story (submove 2.2) is to provide essential background information. In providing background information, authors summarize (and cite) works that influenced their proposed ideas. Because new ideas
nearly always build on earlier contributions, effective writers learn to integrate
background information into their own research stories, highlighting the works
that laid the groundwork for their proposed work. Providing background information also helps authors establish intellectual merit by demonstrating knowledge of pivotal works in their field.
Effective writers also learn to present background information in ways
that further establish the importance of the proposed work (move 2). To
underscore this point, we organize the excerpts that follow around three
approaches for sharing background information. Each approach provides background information and, at the same time, stresses the importance of the proposed work.
As each approach is presented, we use italics to highlight words and phrases
that are particularly effective in conveying importance. These words are commonly used in proposal writing, and we encourage you to use them in your own
writing as well.
Three Approaches to Providing Background Information and Emphasizing Importance
Document interest
Emphasize benefits
Establish need for new knowledge
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407
Important Words
Effective proposal writers use words that stress the importance of their research as they
provide background information.
Document Interest
Your work acquires credibility when you review the literature and show
that your contribution extends from a solid foundation of respected
research.
—Paradis and Zimmerman (1997)
One way authors stress importance as they share background information is to
document widespread interest in the research area (i.e., if others studied it, it
must be important). Slightly different tactics are used depending on how new
the research area is. If the field is already well established, phrases such as longterm interest, renewed interest, extensively studied, or for decades, chemists have studied
are commonly employed. If the field is relatively new, such phrases as emerging
interest, increased attention, previously unstudied, promising new approach, unexplored
area, or an area of mounting concern are more appropriate.
The following excerpts illustrate this approach. Vyvyan (excerpt 12H) establishes the importance of herbicides by (1) acknowledging the historic role of
synthetic herbicides over 50 years, (2) pointing out shifting attention to alternative approaches, and (3) emphasizing that the area has recently opened up to significant research. Gudmundsdottir (excerpt 12I) demonstrates that aryl nitrenes
are important because they have been studied extensively over the last decades.
Moreover, renewed interest has been sparked because aryl nitrenes are ideal candidates for organic magnetic materials. Note, too, in excerpts 12H and 12I, how
the authors incorporate citations to others’ works as they develop their research
stories (the history of weed control in excerpt 12H and the history of aryl nitrenes
in excerpt 12I).
Excerpt 12H (from Vyvyan, 2001)
BACKGROUND AND SIGNIFICANCE
Maximizing the world’s agricultural efficiency depends on controlling unwanted pests—
especially weeds. Synthetic herbicides have met the weed control needs of industrialized nations for over 50 years, but mounting ecological and human health concerns are
shifting attention to alternative weed control technology based on cues from nature.1,2
Allelopathy, the chemical interaction between plants and microorganisms, has likely
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The Research Proposal
been known for thousands of years. This area, however, has only recently opened up to
significant, specific research aimed at determining which natural products are responsible for these interactions.3
Excerpt 12I (from Gudmundsdottir, 2001)
INTRODUCTION
Aryl nitrenes have been studied extensively over the last decades and are used in several
industrial processes such as microlithography.1 Aryl nitrenes have also been used in
photoaffinity labeling bioorganic molecules. The pursuit for organic magnetic material
has sparked renewed interested in nitrene intermediates, which are ideal candidates for
magnetic material because of their high spin properties.2
Spain (excerpt 12J) also builds her research story as she demonstrates interest
in her field. Sixteen studies are cited to document interest, stating that more and
more examples of kinetic-energy-dependent surface dynamics are appearing in the
literature. Key findings from these works are summarized (citations 6–21), providing readers with necessary background information and attesting to the authors’
intellectual merit. Collectively, the cited works point to the importance of the emerging discipline addressed in her proposal, hot atom chemistry.
Excerpt 12J (from Spain, 1997)
More and more examples of kinetic-energy-dependent surface dynamics of reagents
on low temperature substrates are appearing in the literature. A few examples follow.
Although Cl2 does not spontaneously etch Si at room temperature, kinetic-energyenhanced Cl2 does,6–11 as observed by mass spectrometric detection of products. Similar
studies involving F and F2 have appeared in the literature.12–13 The growth of thin films
with pulsed supersonic jets prompted the study of CO2 chemisorption on the Si(100)
surface. The initial sticking coefficient of CO2 on Si(100)2 × 1 was found to be negligible
with thermal CO2 but significant with hyperthermal CO2.14,15
The first direct evidence for the Eley–Rideal mechanism was determined in 1991.16
In that study, it was demonstrated that kinetic-energy-enhanced N(C 2H4)3N reacts with
H on a Pt(111) surface to form an ion. The ion leaves the surface with a translational
energy that depends on the energy of the incident species. In a study of H atoms incident
on D/Cu(111),17,18 direct evidence that HD is formed by the Eley–Rideal mechanism was
found, in part, by varying the translational energy of the H reagent.
Other groups have investigated how incident kinetic energy affects film growth
processes. For example, kinetic-energy-dependent surface trapping probabilities were
measured with hyperthermal beams of alkali ions directed at a Cu surface.19 In general,
trapping efficiency decreases as incident ion kinetic energy increases. However, at lower
incident energies, a minimum trapping probability was observed. Co adsorption to Si(100)
has also been shown to depend on Co translational energy.20 Collectively, these studies
point to the importance of the emerging discipline called “hot atom chemistry.” 17,21
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409
Superscript Numbers
Using superscript numbers is one of three common ways to cite others’ works. (See
chapter 17.)
Similarly, Tuckerman (excerpt 12K) cites works that emphasize widespread
interest in the research area, highlighting, for example, that crystal hydrates have
attracted the attention of crystallographers and spectroscopists over several decades
(46–28, 123–125). Specific benefits of crystal hydrates are touted, including their
possible use as proton conductors (126) and as important media for the study of
proton motion. The latter is currently of interest in the field of low temperature
spectroscopy (127–129).
Excerpt 12K (from Tuckerman, 1999)
Crystal hydrates of strong acids and bases have attracted the attention of crystallographers and spectroscopists over several decades (46–48, 123–125). The interest in these
crystal systems lies in their possible use as proton conductors (126). Moreover, as
proton transfer events often occur in complexes such as H 5O2 and H 3O2, these
systems are important media for the study of proton motion through hydrogen bonds
in a crystalline environment, a process currently of interest in the field of low temperature spectroscopy (127–129).
Italic Numbers in Parentheses
Using italic numbers in parentheses is one of three common ways to cite others’ works.
(See chapter 17.)
Exercise 12.16
Reread excerpts 12H–12K and answer the following questions:
a. What research topic is identified in the opening sentence of each excerpt
(confirming that excerpts follow submove 2.1)?
b. How many works are cited in these excerpts? Comment on how the cited
works help to stress importance, develop the research story, and establish
intellectual merit.
c. Are these excerpts written for a scientific or expert audience? Justify your answer.
d. Of the key words and phrases used in these excerpts to document interest
in the research area, which three are your favorites (i.e., ones that you would
likely use in your own writing)?
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The Research Proposal
Exercise 12.17
Read excerpt 12L and answer the following questions:
a. Briefly describe how the excerpt establishes importance by demonstrating
interest in the research area.
b. In addition to interest, what other features are stressed to emphasize the
importance of combinatorial chemistry?
c. What words and phrases are used to emphasize the importance of the area?
d. Is this researcher proposing work in an established or emerging field?
Explain.
Excerpt 12L (from Hergenrother, 2002)
In the past decade, combinatorial chemistry has exploded onto the scene of modern
science. The pharmaceutical industry quickly adopted this burgeoning technology as
a method to rapidly derivatize and evaluate “lead compounds”—compounds that have
already shown promise is some biological assay. As such, combinatorial chemistry has
often been relegated to a late role in the drug discovery process and is largely thought of
as an “industrial” type of science. However, it is clear that the potential for combinatorial chemistry is much greater than has been realized thus far. Indeed, there exists a real
opportunity for the creative uses of combinatorial chemistry and for new paradigms in
the development and application of combinatorial technologies.
Lead vs. Led
Lead (n.): Pb (an element)
Lead (v.): to show the way
Lead (adj.): serving as a model or leader
Led (v.): past tense and past participle form of lead
The element lead (noun) and the verb led (past tense/past participle) have the same
pronunciation. Be careful not to confuse them in your writing.
Emphasize Benefits
A second way authors stress importance as they share background information is to describe how the research will benefit others. For example, Houser
(excerpt 12M) points to environmental benefits; he makes the case that understanding the process of dentrification can lead to improvements in air pollution,
greenhouse gas production, and eutrophication. Finney (excerpt 12N) points to
Writing the Goals and Importance Section
411
technological benefits; he argues that advances in fluorescent chemosensors can
both simplify measurements and reduce cost, by using much less expensive materials.
Similarly, Lyon (excerpt 12O) emphasizes medical benefits; he investigates bioresponsive gels and points out (as he describes previous accomplishments in the
field) the already remarkable benefits of these gels in drug-delivery systems. Once
again, the literature is cited in each excerpt, serving both to develop the research
story and to establish the intellectual merit of the investigator.
Excerpt 12M (from Houser, 2001)
Copper-Nitrite Reductase (Cu-NiR)
Nitrite reductases (NiRs)—enzymes found in several strains of denitrifying bacteria—
catalyze the one-electron reduction of nitrite anion to nitric oxide (Equation 1).1,2 In
addition to the importance of this process in the global nitrogen cycle (Figure 1), further
incentive for the study of the denitrification process is provided by its environmental
impact, ranging from the production of NO as a pollutant and N2O as a potent greenhouse gas, to lake eutrophication due to farm runoff that contains high concentrations of
nitrates and nitrites.
Excerpt 12N (from Finney, 1999)
There are two primary reasons why a fluorescent chemosensor with visible emission
would be desirable, in addition to its inherent aesthetic appeal. First, it simplifies qualitative experimental measurement: the human eye is sensitive enough to detect extremely
small changes in intensity (the limit of visual detection by a dark-adjusted eye has been
estimated as ≈ 1 nW),22 which would allow a simple visual assessment of whether fluorescence enhancement was occurring in the presence of an analyte. Second, the materials associated with the quantitative measurement of visible light are much less expensive
than those for measurement of UV emission; visible emission would allow the use
of disposable plastic curvettes for fluorescence measurements in the lab and would be
compatible with the least expensive forms of fiber optic technology.
Semicolons (;)
Use semicolons to join two related statements. (See appendix A.)
Excerpt 12O (from Lyon, 2000)
Among the most remarkable responsive gels have been those involving drug
delivery.14,35–37 An artificial pancreas has been developed,13,14,38 as has a secretory granule
mimic.39 In these applications, the gel acts as a drug entrapment matrix in its collapsed
state and then expands in response to temperature or salinity changes thereby releasing the drug to the environment. Others have modified the active sites of a variety of
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The Research Proposal
proteins with short thermoresponsive oligomers 40,41 or have attempted to construct
a hydrogel-based artificial muscle composed of bundled pH-responsive fibers.42 Still
others have created enzyme-polymer conjugates which swell in response to enzyme
activity.43,33 In these cases, the ionic strength or pH of the environment changes as the
enzyme turns over a substrate.
Comprise vs. Compose
See appendix A for more information on these commonly confused words.
Exercise 12.18
Reread excerpts 12M–12O and complete the following tasks:
a. List at least four benefits that the authors have identified in their writing.
Suggest two additional benefits that can be addressed, not identified in these
excerpts.
b. Comment on the number of citations in these excerpts. Give an example of
how the cited works further the research stories and attest to the authors’
intellectual merit.
c. Are these excerpts written for a scientific or expert audience? Justify your
answer.
Exercise 12.19
Read excerpts 12P and 12Q. One excerpt promotes importance by describing a
research area that will have a positive impact on society. The other does so by
highlighting a potentially negative consequence to society. Which is which? What
benefits will research in each area provide to society?
Excerpt 12P (from Fairbrother, 2000)
Organic surfaces are encountered in a wide range of situations where interfacial
properties impact a material’s performance characteristics.1 For example, a polymer’s
interfacial characteristics determine chemical and physical properties such as permeability, wettability, adhesion, friction, wear, and biocompatibility.1–3 However, polymers
frequently lack the optimum surface properties for these applications.1,4 Consequently,
surface modification techniques have become increasingly desirable in technological applications of polymers.5,6 These processes are capable of tuning the properties of
Writing the Goals and Importance Section
413
organic surfaces without affecting the bulk composition, thereby transforming inexpensive raw materials into highly valuable fi nished products.7 Within the field of surface
modification treatments, vacuum based strategies, including plasma processing,8 have
become a preeminent means for tailoring the properties of organic surface.9 Compared
to wet-chemical treatments for surface modification, these technologies are dry, fast, and
environmentally benign.10
Excerpt 12Q (from Aga, 2002)
Approximately 19 million pounds of antibiotics are used each year in U.S. cattle,
hogs, poultry, and other food animals; this is over 40% of the antibiotics sold in the
U.S. (17). The routine use of antibiotics on farms to accelerate growth and prevent
diseases has been speculated to have created strains of disease-causing bacteria that
are resistant to antibiotics, which in turn infect more human beings every year (18).
Because of the widespread use of antibiotics in livestock production, it would not be
surprising to see antibiotic contamination of the aquatic environments situated near
animal feedlots and confi nements. The presence of antibiotics in water resources
is suspected to contribute to the proliferation of resistant microorganisms. It is not
clear how much of these chemicals fi nds its way into the surface water near livestock
operations.
Exercise 12.20
Reread excerpt 12P and answer the following questions:
a. Examine the ways in which the author creates linkages, adds emphasis, and
contributes to the fluency of his writing with such words and phrases as for
example, however, and consequently. Consult table 6.6 and determine the functions of these words.
b. The word thereby is also used in excerpt 12P; it is not listed in table 6.6.
Nonetheless, consult the table to assist you in determining its function
in the excerpt.
Establish Need for New Knowledge
A third way authors establish importance as they share background information
is to highlight the need for new knowledge. Few scientists can resist the appeal
of new knowledge, and a project will likely be successful if it has the potential to
offer new insights, depth, or detail. For example, Fairbrother (excerpt 12R) uses
this approach when he states that the surface science associated with polymer
modification treatments remains virtually unexplored. He goes on to cite a panel
report that attests both to this lack of mechanistic understanding and to the need for
concerted experimental research in this area.
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The Research Proposal
Excerpt 12R (from Fairbrother, 2000)
Despite their technological importance, the surface science associated with polymer
modification treatments remains virtually unexplored. This lack of a mechanistic understanding can be ascribed to the complexity of typical reactive media present in modification treatments, as well as to the heterogeneous/polyfunctional nature of the organic
surface. In the absence of a molecular level understanding, modification strategies have
developed along empirical lines. The lack of a fundamental mechanistic understanding
of surface modification processes has been highlighted in a recent panel report.11 The
panel notes that to develop an understanding of the physical and chemical processes
accompanying surface modification treatments, concerted experimental research is
required.11
Similarly, Rose-Petruck (excerpt 12S) asserts that current knowledge of ultrafast
molecular motions is not sufficient, and more detailed knowledge of these motions
is of fundamental importance for understanding reaction mechanisms. Warren
(excerpt 12T) suggests a better mechanistic understanding of metal-catalyzed processes is needed and may be possible with new insights into the patterns of selectivity of metal-catalyzed processes. Walker (excerpt 12U) cites several different
phenomena (chemical transport, surface reactivity, electron transfer, and selfassembly) that could benefit from deeper insights into interfacial solvation interactions. Such insights could be gained through predictive models of solvent-solute
interactions.
Excerpt 12S (from Rose-Petruck, 2000)
A fundamental goal of chemical research has always been to understand the reaction
mechanisms leading to specific reaction products. Reaction mechanisms, in turn, are a
consequence of the structural dynamics of molecules participating in the chemical process, with atomic motions occurring on the ultrafast timescale of femtoseconds (10 –15 s)
and picoseconds (10 –12 s). Although kinetic studies often allow reaction mechanisms as
well as the kind and properties of reaction intermediates to be determined, the obtained
information is not sufficient to deduce the ultrafast molecular dynamics. Because these
ultrafast motions are the essence of every chemical process, detailed knowledge about
their nature is of fundamental importance.
Excerpt 12T (from Warren, 2002)
Carbene, nitrene, and oxo complexes of Mn–Cu represent challenging synthetic
targets that would enable a better mechanistic understanding of metal-catalyzed
cyclopropanation, aziridination, and oxidation reactions promoted by these complexes. By offering insights into the patterns of selectivity of these complexes, these
studies may pave the way toward a rational design of a future generation of more
efficient catalysts.
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Excerpt 12U (from Walker, 2001)
Given that interfacial solvation affects chemical transport,16 surface reactivity and
electron transfer,17–20 and macromolecular self-assembly,21 predictive models of solventsolute interactions near surfaces will afford researchers deeper insights into a host of
phenomena in biology, physics, and engineering. Research in this area should aid efforts
to develop a general, experimentally tested, and quantitative understanding of solutionphase surface chemistry.
Exercise 12.21
Read excerpt 12V. What unique opportunity to gain new knowledge is described?
Can you think of other research projects that may be unique because of their
location in space or time?
Excerpt 12V (from Harpp, 1998)
OBJECTIVES AND SIGNIFICANCE
The Galápagos Islands provide a unique opportunity to study detailed lithospheric
structure and processes, primarily because of their location adjacent to a mid-ocean
ridge system. They lie on the Nazca plate, just south of the Galápagos Spreading Center
(GSC), with an east-west trending ridge serving as the boundary between the Nazca and
Cocos plates (Figure 1). Hotspots and the magmas they produce serve as effective probes
of the earth’s deep interior, particularly when examined in conjunction with geophysical
exploration.
Between vs. Among
See appendix A for more information on these commonly confused words.
Exercise 12.22
Read excerpt 12W. Tuckerman uses all three approaches for establishing importance; he demonstrates interest, emphasizes a benefit, and establishes the need for
new knowledge. Find a sentence that illustrates each approach.
Excerpt 12W (from Tuckerman, 1999)
Several hundred to several thousand feet beneath the ocean floor in permafrost and
continental edge regions lies a potentially vast source of natural gas: in excess of 1016
cubic meters of gas hydrates, consisting largely of methane clathrate (53–55). Gas
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The Research Proposal
hydrates are nonstoichiometric compounds consisting of hydrogen-bonded water
molecules in a cagelike structure, which traps small-diameter gas molecules. The
methane clathrate, in particular, is stable in the pressure range of roughly 20–40 MPa
and temperature range of 175–250 K (55). Interest in these vast beds of crystallized gas
hydrate is rapidly increasing for several reasons. They constitute perhaps the largest
untapped source of hydrocarbon energy available. They also pose a possible threat as
an enormous source of greenhouse gas. As global warming continues to cause oceanic
temperatures to rise and permafrost regions to recede, the risk of destabilization of the
beds increases and with it the risk of releasing large quantities of trapped greenhouse
gas into the atmosphere. Given the potential importance of gas hydrates, it is vital that
we expand our knowledge of their physical properties, which as yet, are only poorly
understood.
Analyzing Writing
We conclude our analysis of move 2 with a brief summary of writing features
common in this move. We placed pointers near selected excerpts in this move to
call your attention to the following:
■
subject–verb agreement (passages P6 and P7)
■
formatting figures (excerpt 12G)
■
in-line citations (excerpts 12J and 12K)
■
lead vs. led (excerpt 12L)
■
semicolons connecting two sentences (excerpt 12N)
■
comprise vs. compose (excerpt 12O)
■
between vs. among (excerpt 12V)
To test your knowledge of some of these features, complete exercises 12.23–12.25.
Exercise 12.23
In each sentence, what is the subject of the italicized verb? Does the verb form
agree with the subject? If not, correct the verb form.
a. The preparation of new materials at molecular-length scales and in different
molecular orientations is the subject of much current research.
b. The increased use of chemicals in agricultural products and antibiotics have
raised public concerns.
c. Thermal conrotatory 4π ring opening of aziridines and epoxides is a wellrecognized method of generating azomethine and carbonyl ylides.1 (From
Johnson, 2003)
Writing the Goals and Importance Section
417
d. How much of these chemicals finds its way into the surface water near livestock operations is not clear. (Adapted from Aga, 2002)
Exercise 12.24
Select the correct word in each of the following sentences:
a. Combinatorial chemistry has lead/led the chemical industry in developing
lead/led antibiotic compounds.
b. Artificial muscles are composed of/comprised of pH-responsive fibers.
c. Among/Between the three possibilities, only the two involving active sites will
be considered.
Exercise 12.25
Consider the following passage adapted from Aga (2002) that contains
five sentences and no semicolons. Rewrite the passage so that two pairs of
adjacent sentences are connected by semicolons to emphasize their close
relationships.
After elution from the SPE cartridges, the eluents will be evaporated slowly under nitrogen gas. The concentrated samples containing metolachlor will be analyzed by GC/MS
while the fractions containing the polar metabolites will be analyzed by HPLC. Both the
GC and HPLC will be equipped with chiral columns. For GC/MS, a fused silica column
coated with tert-butyldimethylsilyl--cyclodextrin will be used. This column has been
shown to partially separate metolachlor isomers (13).
Lastly, we briefly consider verb tense and voice used in move 2. As shown in
table 12.5, past and present tenses and present perfect may all be used. Past
tense and present perfect are used to provide background information (work
done in the past), typically in passive voice. Passive voice allows the writer to
focus on the science rather than the scientist:
Present perfect–passive (more common) Aryl nitrenes have been studied
extensively over the last decade.
Present perfect–active (less common)
Scientists have studied aryl nitrenes
extensively over the last decade.
Present tense and active voice are commonly used for statements of importance,
knowledge, or fact. We is not used in move 2 because the proposed work is not
mentioned.
418
The Research Proposal
Table 12.5 Common functions of different verb tense–voice combinations in move 2 of the Goals and
Importance section.
Function
Tense–Voice
Combination
Example
Present background
information (work
done in past)
Past–passive
The first direct evidence for the Eley-Rideal
mechanism was determined in 1991.16 (From
Spain, 1997)
Present perfect–passive
An artificial pancreas has been developed.13,14,38
(From Lyon, 2000)
Stress importance
Present–active
The catalytic transformation of organic
molecules is of tremendous importance.
Report existing
knowledge/facts
Present–active
Nitrite reductases catalyze the one-electron
reduction of nitrite. (From Houser, 2001)
The Galápagos Islands sit on a large volcanic
platform in the Pacific Ocean. (From Harpp,
1998)
Exercise 12.26
The following sentences from excerpt 12J use past tense, present tense, and/or
present perfect correctly. Identify which is used in each italicized segment. What
general purpose is conveyed? (Consult table 12.5, if needed.)
a. Although Cl2 does not spontaneously etch Si at room temperature, kinetic-energyenhanced Cl2 does,6–11 as observed by mass spectrometric detection of products.
b. In general, trapping efficiency decreases as incident ion kinetic energy
increases. However, at lower incident energies, a minimum trapping probability was observed.
c. Other groups have investigated how incident kinetic energy affects film growth
processes.
d. Co adsorption to Si(100) has been shown to depend on Co translational energy.20
e. Collectively, these studies point to the importance of the emerging discipline
called “hot atom chemistry.” 17,21
Exercise 12.27
Rewrite the following sentences so that they are in passive voice and emphasize
the science rather than the scientist:
a. We describe two practical tools: the Swain–Schaad Exponential relationship
and the temperature dependency of KIEs.
Writing the Goals and Importance Section
419
b. People have recognized allelopathy, the chemical interaction between plants
and microorganisms, for hundreds of years.
c. Chemists have studied aryl nitrenes extensively over the last decades and
have used them in several industrial processes such as microlithography.1
12C Writing on Your Own: Introduce and Develop the Research Story
Draft move 2 of your Goals and Importance section. In the first sentence, identify the
research area in general terms. (Do not introduce your specific research project.) Develop
the research story in the next few paragraphs. Explain fundamental concepts and provide
essential background information, using the notes that you prepared in Writing on Your
Own task 12A. Share what you learned from your literature review, and its importance, with
your readers.
Explain at least one general concept at a scientific or general audience level (keeping
in mind that reviewers may not be familiar with your research area). Include an illustration,
if applicable. Provide relevant background information at a more advanced level. Be sure
that you paraphrase and incorporate citations appropriately. As you share background
information, stress the importance of the research using at least one of the three suggested approaches: document interest, emphasize benefits, and establish a need for more
knowledge.
Remember that this move gives you the opportunity to demonstrate your grasp of the
research area and establish your intellectual merit as a researcher, two keys to an effective
proposal.
Move 3: Introduce the Proposed Work
Move 3 shifts the focus from the general research topic and others’ works (moves
1 and 2) to the specific work proposed by the author(s). The transition is typically
accomplished in two submoves (figure 12.1). Normally, move 3 is not given its
own heading; rather, move 3 and its submoves continue under the heading for
move 2. (Excerpt 12X is an exception to this practice.)
In the first submove, the need for the proposed work is established in one or
two gap statements. Gap statements, as the name implies, point out gaps in the
field, in the form of questions that need to be answered, techniques that need to
be developed, areas that need further exploration, and so forth. In the second
submove, the gap is filled (at least in part) by the proposed work. In these two
submoves, the focus of the proposal shifts from the general research area to the
more specific research project, setting the stage for the next section of the proposal, Experimental Approach (see chapter 13).
420
The Research Proposal
Gap Statements
The gap statement can suggest
■
questions that need to be answered
■
techniques that need to be improved or developed
■
areas that need to be explored
and much more. (See table 6.1.)
Analyzing Excerpts
We are now ready to examine gap and fill-the-gap statements in authentic proposals. Because these two statements work as a pair, we examine them together.
Four excerpts are included; for clarity, we have italicized the words that signal the
beginning of the gap and fill-the-gap statements in each excerpt.
Excerpt 12X uses lists to delineate both the gap (the experimental challenge) and
fill-the-gap statements (facing the challenge); excerpts 12Y–12AA use narrative form.
In each case, the depiction of the work following the fill-the-gap statement is brief,
laying the groundwork for a more detailed description of the proposed work.
In these excerpts, the authors assist the reader by signaling gap and fill-thegap statements. To signal a gap statement, the authors forewarn the reader of
obstacles and difficulties or use such terms as unfortunately. To indicate that a fillthe-gap statement is coming, the authors use different forms of propose or other
words indicating intent.
The four excerpts also illustrate the use of personal pronouns (specifically,
I and we) in the fill-the-gap statement. One author (Spain) uses I and we (“I propose”
and “we will employ”). All others use only we (“We propose to address”, “We will
synthesize”, “we intend to pursue”). Using both I and we in a single proposal is not
uncommon, particularly in proposals that are written by one investigator (e.g., the
CAREER proposal). A sole author (the PI) is proposing the work (hence, I), but a
group of individuals (the PI, students, postdocs, and collaborators) will conduct
the work (hence, we).
Exercise 12.28
Read excerpts 12X–12AA and answer the following questions:
a. What words do the authors use to signal gaps and gap fillers?
b. Consider the different ways in which the excerpts are formatted (i.e., the lists
in 12X and continuous text in 12Y–12AA). Which form of presentation do
you prefer? Why?
Writing the Goals and Importance Section
421
Excerpt 12X (from Kohen, 2002)
The Experimental Challenge
There are three main obstacles to any attempt to experimentally evaluate the effect of enzyme
dynamics on covalent bond activation. Namely, it is difficult to
1. extract effects on the chemical step (e.g., C–H bond cleavage) and its transition state
within the multi-step kinetic cascade of enzyme catalysis.
2. measure the motion of a protein on a wide range of time scales, with high regional
resolution.
3. interpret information on protein dynamics as vibrational modes coupled to the
reaction coordinate. NMR relaxation experiments, for example, yield little information on the direction of internal motion. Experimental correlation between
the rigidity of proteins (as measured by H/D amide exchange)28 and the degree
of H-tunneling in the reactions also offers little information about which protein
motions are involved.
Facing the Challenge
We propose to address these obstacles by
1. studying the chemical step within a complex kinetic cascade. Hydrogen tunneling
and the coupling of primary and secondary hydrogens at the same carbon center
will be used as probes of the C–H bond activation. . . . Theoretical studies predict
that dynamic processes will markedly affect these phenomena in enzyme-catalyzed
reactions.26.29
2. measuring the motion of a protein. The protein dynamics will be measured by various techniques, primarily focusing on the ps-ns time scale. DHFR is small enough to
allow NMR relaxation experiments.
3. interpreting the data. DHFR is a small enzyme that catalyzes C–H bond cleavage. Not only experimental data acquisition but also several theoretical approaches
benefit from the small size of the enzyme. Molecular dynamics simulation (MD), for
example, can assist in the assessment of DHFR dynamics,35 although it is currently
limited to a few ns.36 We propose to test several theoretical disciplines while attempting to correlate H-transfer data to dynamic fluctuation data. These attempts should
yield predictions that we will examine experimentally.
Parallelism in Enumerated Lists
See appendix A.
Excerpt 12Y (from Spain, 1997)
The ever decreasing dimensions of semiconductor devices impose paradoxical requirements on the plasma etching and deposition processes involved in their manufacture.4
422
The Research Proposal
Low substrate temperatures are required to prevent thermal damage to layers already
fabricated, while, at the same time, low energy plasma conditions are required to limit
damage by high energy ion implantation. Unfortunately, many films, especially metal chalcogenides, require high temperature annealing (typically 300 to 500 °C) after deposition in order to
obtain crystalline films, violating the low temperature requirement. The use of kinetic-energyselected neutral beams, however, may open the door to metal chalcogenides deposition,
allowing deposition at low substrate temperatures without damage from
high energy ion exposures.
To explore this potential, I propose to study the fundamental chemical dynamics of materials
deposition by varying the kinetic energy of reagent atoms impinging on a surface. Specifically,
we wish to understand the growth and nucleation of transition metal chalcogenide thin
films on chemically modified and solid surfaces as a function of reagent kinetic energy.
We will employ laser-induced vaporization by back illumination (LIVBI) to produce
translationally hot and neutral metal atom beams. In this method, which has successfully grown many types of metal-containing films including superconductors, the vaporized material is generated as a plasma containing electrons, neutral and ionized atoms,
molecules, and perhaps some clusters. Therefore, LIVBI is ideal to study the fundamental aspects of film growth because the beams are directed, neutral, and kinetic-energy
resolved from near thermal to hyperthermal.
Excerpt 12Z (from Vyvyan, 2001)
Another obstacle to advancing this field is the minute quantities of the active compounds that
can be isolated from the natural sources. . . . For example, the heliannuols (1–11, Figure 1)
are a promising group of phenolic allelochemicals that exhibit activity against dicotyledon plant species (13). Heliannuols A and D (1 and 4, respectively) are the most active
members of the family with effective concentrations of 10 –4 to 10 –9 M. . . . The recent
isolation of heliannuols F–K (6–11), in which over 6 kg of sunflower leaves was required
to obtain just 1–2 mg of each pure compound, clearly illustrates their scarcity (16).
Thus, a synthetic source of promising allelochemicals is essential if we are to comprehensively study the agent’s mode of activity and establish its basic structure-activity
profile. The proposed work addresses this need. We will synthesize alleopathic natural products isolated from the sunflower (the heliannuols), and structurally related compounds,
in optically pure form based on biomimetic phenol-epoxide cyclizations. The bioactivity of the targets and intermediates will be evaluated through laboratory tests on plant
germination and growth. Bioassays will be performed on the synthetic intermediates
to allow for the development of a preliminary structure-activity profile for these novel
natural herbicides.
Compound Labels
To conserve space, chemical names are often represented by bolded numbers (e.g., 4) or
numbers and letters (e.g., 4a). Like other abbreviations, they are defined at first use, often in
a figure or table. (See appendix A.)
Writing the Goals and Importance Section
423
Excerpt 12AA (from Finney, 1999)
Despite the remarkable progress in the field of molecular recognition, it is still extremely
difficult to predict a priori the structure of a selective, high-affinity ligand for a metal ion
such as Hg 2 . The approach we intend to pursue is to take advantage of combinatorial chemistry methods—a collection of technical advances that allow one to seriously consider
undertaking the synthesis of hundreds or even thousands of compounds simultaneously 29 —to carry out the parallel synthesis of a set of 100 potentially selective highaffinity fluorescent chemosensors for mercury.
Exercise 12.29
Read excerpt 12BB and answer the following questions:
a. Identify the gap and fill-the-gap statements.
b. What word(s) does the author use to signal the gap and gap filler?
c. Does the author use personal pronouns as you might expect? Explain.
Excerpt 12BB (from Rose-Petruck, 2000)
However, atom motions cannot be unambiguously “imaged” by time-resolved optical spectroscopic methods as they do not directly measure the structural dynamics but
instead characterize energetic properties. Consequently, novel methods that enable
the direct measurement of molecular motions during chemical processes are needed.
Furthermore, chemical reactions often occur in solution and, consequently, it is
desirable that such methods are applicable to chemical processes in the liquid
phase.
I propose to develop and apply such methods, based on ultrafast X-ray absorption
spectroscopy, to study the ultrafast molecular motions of organometallics in solutions.
In particular, initial studies will focus on photo-induced ligand dissociation and substitution reactions of transition metal carbonyls and related compounds in various solvent
systems.
Analyzing Writing
We conclude our analysis of move 3 by summarizing writing conventions commonly observed in this move. We used pointers near selected excerpts to point
out the following:
■
parallelism in enumerated lists (excerpt 12X)
■
labels for chemical names (excerpt 12Z)
Test your knowledge of these conventions by completing exercises 12.30 and 12.31.
424
The Research Proposal
Exercise 12.30
Reread the lists in excerpt 12X. Specify examples that illustrate parallelism in
language, numbers, and punctuation.
Exercise 12.31
Glance ahead to excerpts 13L and 130. Both excerpts include bolded numbers.
What purpose do these bolded numbers serve?
We close our discussion of move 3 by analyzing common verb tense and voice
combinations used in this move (table 12.6). Gaps are often stated in present
tense (in active and passive voice), sometimes in combination with a present perfect–passive statement; fill-the-gap statements are usually in present or future
tense and active voice. Personal pronouns (I or we) are common in fill-the-gap
statements.
Table 12.6 Common functions of different verb tense–voice combinations in move 3 of the Goals and
Importance section.
Function
Tense–Voice
Combination
Example
Identify a gap in the field
Present–active
Another obstacle is the . . .
Present–passive
Consequently, new methods are
needed that . . .
Present perfect–passive
Although . . . has been studied in
depth, little is known about . . .
Present–passive
Fill the gap by introducing
proposed work
Present–active
I propose to overcome these
difficulties by . . .
Future–active
We will overcome these difficulties
by . . .
Exercise 12.32
Read passages 1–3 below, in which words in the gap statements have been
deleted:
a. Suggest the words that have been deleted so that the gap statements
read well.
b. Identify the verb tense and voice combinations used in the gap statements.
Writing the Goals and Importance Section
425
1. Aside from their applications to polymer systems (see below), the ____
of prior published research involving thermotropic liquid-crystal (LC)
solvents for controlled crystallization and materials synthesis is striking. A detailed literature search for applications of thermotropic LCs
to fi lm growth revealed a single citation (a patent) describing a method
for controlling molecular alignment in an organic fi lm. (From Patrick,
2000)
2. To date, effective, positive-signaling fluorescent chemosensors have been
developed for cations such as Ca 2 and Zn 2 . 4 ____, the development
of fluorescent chemosensors for heavy metals . . . or small organic molecules . . . generally does not exist. (Adapted from Finney, 1999)
3. The bent plume model does not take into consideration any plume-ridge
interaction, except at the most vague of levels (Harpp, 1995). This is
primarily due to the ____ data from this area; the observed patterns
are ____ complex to draw any solid conclusions with such sparse
sampling. (From Harpp, 1998)
Exercise 12.33
Integrate each set of information (set A and set B) into a concise and effective gap
statement:
Set A (adapted from Gunes et al., 2002)
■
Controlled-atmosphere (CA) storage can extend the storage life of fruits and
vegetables by decreasing metabolism and suppressing postharvest decay.
■
Initial CA treatments with N2 gas have been shown to improve cranberry
storage life by reducing fungal decay (12).
■
Researchers have never examined the effect of CA conditions on the level of
antioxidants found in cranberries.
Set B (adapted from Yamashita et al., 2004)
426
■
The unique physicochemical properties of polyfluorinated compounds
(PFCs) render several challenges to analytical chemists endeavoring to measure PFCs at trace levels.
■
One of the major problems associated with trace level analysis of perfluorinated acids is background contamination in the analytical blanks. Because
of the contamination in blanks, the limits of detection (LOD) of perfluorochemicals in water samples are high, in the range of several tens to hundreds
of ng/L to a few μg/L (11–15).
The Research Proposal
■
Contamination sources of PFCs in laboratories have not been well characterized. Two distinct sources of contamination, instrumental and procedural,
are expected in PFC analysis.
■
The current study improves PFC methods by reducing the above-mentioned
sources of blank contamination.
12D Writing on Your Own: Introduce Your Proposed Work
You are nearly ready to complete the first draft of the Goals and Importance section of
your proposal, but first you must introduce your proposed work. Think about the gaps
that others’ works have left. Focus on those gaps, and then briefly introduce your work by
showing how it will fill those gaps.
12E Writing on Your Own: Complete the Opening Section
Combine the three moves of your Goals and Importance section (from the previous
Writing on Your Own tasks).
Revise and edit the entire section, paying careful attention to audience (e.g., level of
detail, word choice), organization, writing conventions (e.g., verb tenses, voice, personal
pronouns, formatting of lists, and citations), and grammar and mechanics (e.g., parallelism,
punctuation). Revise the Goals and Importance section so that the individual parts work
together as one document.
You may want to consult chapter 18 for proofreading tips. If possible, have a colleague
peer review (formally or informally) the section before turning it in to your instructor. Make
time to incorporate any feedback that you receive.
Chapter Review
Check your understanding of what you’ve learned in this chapter by defi ning
each of the following terms, in the context of this chapter, for a friend or colleague
who is new to the field:
fill-the-gap statement
goals
parallels lists
formal vocabulary
intellectual merit
research story
gap statement
objectives
SAM test
Writing the Goals and Importance Section
427
As a review, try explaining the following to a friend or colleague who has not yet
given much thought to writing the Goals and Importance section of a research
proposal:
■
Main purpose of the Goals and Importance section
■
Differences between goals and objectives
■
Role of enumerated lists
■
Three tangible ways to emphasize importance
■
Three approaches to defining gaps in the field
■
Ways to establish intellectual merit
■
Value of word choice
Additional Exercises
Exercise 12.34
Consider the following list adapted from Vyvyan’s (2001) research proposal. We
have intentionally added errors in parallelism to his list. Revise the list to correct
these errors.
The specific objectives of the proposed work are as follows:
1. to synthesize the heliannuols, allelopathic natural products isolated from the sunflower, in optically pure form.
2. We also plan to perform bioassays on synthetic intermediates and target compounds
to allow for development of a preliminary structure-activity profile for these novel
herbicides.
3. Important natural products structurally related to the heliannuols will also
be synthesized in optically pure form (e.g., helinorbisabone, heliespirone, and
helianane);
4. And finally, to use the synthetic methods developed to prepare simplified structural
analogues of the heliannuols that may retain allelopathic activity.
Exercise 12.35
Correct errors in grammar, punctuation, and wording so that the following sentences are more in line with conventional writing practices. To help you with this
exercise, we have indicated the submove for each sentence.
a. [Submove 2.2] Scientists have studied extensively the mechanism of cyclization.
428
The Research Proposal
b. [Submove 2.2] Researchers have explored a variety of synthetic routes for the
preparation of carbene and nitrene complexes.
c. [Submove 3.1] However the development of fluorescent chemosensors for
heavy metals remain an important yet elusive goal. (Adapted from Finney,
1999)
d. [Submove 3.1] Despite their technological importance the surface science associated with polymer modification treatments remained virtually
unexplored.
Exercise 12.36
Read over the combined Results and Discussion section in excerpt 4A, written
for a journal article. In one or two sentences, summarize the key findings of that
study as they might appear in submove 2.2 (provide essential background information) of a research proposal. Refer to Writing on Your Own task 6A for tips on
paraphrasing.
Exercise 12.37
Consider the following sentences taken from excerpt 12J. Using table 12.5,
identify and justify the tense used for the italicized verbs:
a. It was demonstrated that kinetic-energy-enhanced N(C2H4)3N reacts with H on
a Pt(111) surface to form an ion.
b. In a study of H atoms incident on D/Cu(111),17,18 direct evidence that HD
is formed by the Eley–Rideal mechanism was found, in part, by varying the
translational energy of the H reagent.
c. However, at lower incident energies, a minimum trapping probability was
observed.
Exercise 12.38
Check the following sentences for subject–verb agreement. Correct those
sentences with faulty subject–verb agreement; write “OK” for sentences that are
correct. Refer to appendix A for help, when needed.
a. In these cases, the ionic strength or pH of the environment change as the
enzyme turns over a substrate. (From Lyon, 2000)
b. Most of the theoretical work regarding the utility of time-resolved photoelectron angular distributions to probe electronic, vibrational, and
Writing the Goals and Importance Section
429
rotational dynamics has also concerned neutral photoionization. (From
Sanov, 2002)
c. Crystal hydrates of strong acids and bases have attracted the attention of
crystallographers and spectroscopists over several decades (46–48, 123–125).
(From Tuckerman, 1999)
d. The pressure to provide new information on the fate of pesticides in the
environment have become a monumental task for government and industry.
(Adapted from Aga, 2002)
e. The catalytic transformation of organic molecules are of tremendous importance on laboratory and industrial scales. (Adapted from Warren, 2002)
Exercise 12.39
Rewrite the following excerpt (adapted from Houser, 2001) to make it more
concise:
This type of copper cluster has not previously been observed in any metalloprotein.
Despite the fact that the structure of this important crystal has been solved, much
remains for scientists to learn about the physical, spectroscopic, and chemical properties of the Cu Z catalytic center. For example, we could ask ourselves questions such
as these: First of all, are there copper-copper bonds present in the cluster? Second,
why are four copper ions needed for a two-electron reduction? (78 words; aim for
62 words)
Conciseness
See appendix A and chapter 2.
Exercise 12.40
Consider the following passage adapted from Dyer’s (2001) research proposal.
We have intentionally added errors to the passage. Revise the passage so that it is
more concise and has no punctuation errors.
We are currently initiating three research projects that include: (1) the synthesis of
reflective liquid crystal/polymer composite fi lms, (2) a study of microphase separation
in hyperbranched block copolymers, and (3) the design and synthesis of polar
organic thin fi lms, which is the subject of this proposal. (47 words; aim for
41 words)
430
The Research Proposal
Exercise 12.41
Read the following research proposal passages. Assign each passage to the appropriate submove in move 2 (establish importance) or move 3 (introduce the proposed work). Refer to figure 12.1, if needed. Justify your answer.
a. Two separate combinatorial approaches will be taken to find ligands for
apoptotic proteins: (1) A focused library of compounds will be synthesized
on the solid phase that targets the cysteine protease activity of the caspases.
(2) A primary library of compounds will be synthesized and screened for
selective binding to the various regulators of apoptosis. The size of the libraries will initially be limited to 10,000 compounds such that the structure
of any hits can be elucidated by simple mass spectrometric analysis. (From
Hergenrother, 2002)
b. The catalytic transformation of organic molecules is of tremendous importance on laboratory and industrial scales. Not only do catalysts accelerate
chemical reactions of interest and enhance product selectivity, they allow
chemical transformations to be performed with increased efficiency, minimized waste, and lower energy consumption.1,2 A vast majority of products of
the chemical industry, from bulk to fine chemicals, involve catalysts at some
stage of their manufacture. (From Warren, 2002)
c. To date, effective, positive-signaling fluorescent chemosensors have been
developed for cations such as Ca 2 and Zn 2 . 4 However, the development of
fluorescent chemosensors for heavy metals, which typically quench fluorescence, or small organic molecules for which simple binding motifs generally
do not exist, remain an important yet elusive goal. (From Finney, 1999)
d. Fourier-transform ion cyclotron resonance mass spectrometry (FTICR) is a
high-resolution, high-sensitivity technique that allows the entrapment and
detection of gas phase species.17,18 Gas phase ions are trapped in a magnetic
field, much like a reactant sits in a fl ask in solution. (From Lee, 2001)
Exercise 12.42
Reflect on what you have learned from this chapter. Select one of the reflection
tasks below and write a thoughtful and thorough response:
a. Reflect on the moves generally included in the Goals and Importance section
of a research proposal. (Refer to figure 12.1.)
■
■
■
Which of the moves do you think has the greatest potential to sway the
opinion of a funding agency?
Which move do you think requires the greatest effort on the part of the
writer? Explain.
Which move might be the most challenging to write? Why?
Writing the Goals and Importance Section
431
b. Reflect on the power of language in the Goals and Importance section of a
research proposal.
■
■
■
Based on your reading of the excerpts in this chapter, what specific
types of vocabulary do you intend to incorporate into your own research
proposal?
What particular phrases caught your attention in the chapter? Which
phrases do you want to try to include in your own written work?
What kind of language can you use to emphasize your intellectual merit
as a researcher?
c. In most research proposals, investigators communicate the importance of
the topic by demonstrating interest, emphasizing benefits, and establishing a
need for more knowledge in the area.
■
■
■
432
Of the three typical ways of communicating importance, which do you
think has the potential to be most persuasive? Why?
How did you (or do you plan to) emphasize the importance of your topic?
If you had to rate your importance statement(s) on a scale of 1–10 (1 least
persuasive, 10 most persuasive), what would your rating be? Explain.
The Research Proposal
13
Writing the Experimental Approach Section
A research proposal must present an effective argument that will persuade
those who read and evaluate proposals . . . that the research proposed is
significant, that the methods of pursuing this research are well designed,
and that the researcher is in fact capable of carrying out the research.
—Beal and Trimbur (2001)
This chapter focuses on writing the experimental section of the Project
Description, the section in which you tell readers how you will conduct the
proposed work. Unlike the experimental section of a journal article, which is
written largely after a work has been completed, here you describe proposed
methodology. Reviewers, after reading this section, should be convinced that
the work is plausible and that the investigator has the background and expertise
necessary to carry out the proposed work. By the end of this chapter, you should
be able to do the following:
■
Know ways to establish your expertise as a researcher
■
Be able to share and build on preliminary results
■
Present your proposed research in a logical order
■
Identify obstacles in your proposed research plan
Staying on Track
This chapter covers what is normally presented in the second main section of the Project
Description.
Common headings in this section are
EXPERIMENTAL APPROACH (level 1)
Prior Accomplishments (level 2)
Preliminary Results (level 2)
Proposed Methodology (level 2)
Objective 1. (level 3)
Objective 2. (level 3)
As you work through the chapter, you will write the Experimental Approach
section of your own proposal. The Writing on Your Own tasks throughout the
chapter guide you step by step as you do the following:
13A Share prior accomplishments
13B Share preliminary results
13C Describe your proposed methods
13D Complete the Experimental Approach section
Reading and Analyzing Writing
We begin with excerpt 13A, part of an Experimental Approach section that you
can read and analyze on your own. Excerpt 13A is a continuation of excerpt 12A,
where Aga makes the case that we need to better understand the stereochemistry
of metolachlor, a widely used herbicide and potential carcinogen, as it degrades
in soil. In excerpt 13A, she describes two specific research objectives needed to
accomplish this task.
Exercise 13.1
As you read and analyze excerpt 13A, complete the following tasks:
a. Explain why Aga organized this section of her proposal in two parts.
b. Identify the moves in this excerpt, making use of the suggested headings in Staying on Track above. Note that this excerpt is only part of an
Experimental Approach section.
c. Determine what verb tense–voice combination predominates in this excerpt.
Excerpt 13A (Aga, 2002)
Proposed Methodology
Analytical Methods Development. A solid-phase extraction (SPE) method that will
isolate and fractionate metolachlor and its oxanilic acid (OXA) and ethanesulfonic acid
(ESA) metabolites from soil and water will be developed. The SPE method will be used
434
The Research Proposal
to separate the compounds into sub-classes to simplify the separation of each compound
into its individual isomers by high-performance liquid chromatography (HPLC) or by
GC/MS. SPE will be used to isolate metolachlor and its degradation product from soil
and aqueous samples by adsorbing these compounds into a non-polar material, such as a
C-18 resin, followed by elution with organic solvents. With properly designed SPE
procedures, closely related compounds may be separated into fractions by using different eluting solvents of varying degrees of polarity. Because SPE is also a pre-concentration technique, the method detection limit for the quantification of individual isomers
could be improved by several orders of magnitude.
Several commercially available SPE packing materials, such as silica-based C-18,
polymer-based reversed-phase hydrophilic-lipophilic balance (HLBTM), and graphitized
carbon cartridges will be tested for their potential use in the isolation of the target
compounds. Different combinations of organic solvents and buffers of varying pHs will
be used to determine the optimum eluting solvent that gives maximum recovery of the
analytes.
Our previous work showed that alachlor, a compound that is structurally similar to
metolachlor, could be separated from its acidic metabolites using a C-18 SPE cartridge
(12). However, this procedure does not allow the separation of the OXA and the ESA.
Thus, different adsorption mechanisms and solvent systems will be explored to separate
the analytes into three fractions: metolachlor, OXA, and ESA. This procedure is depicted
in Figure 4 [not included in excerpt]. The SPE procedure will be necessary to avoid overlapping of the eight isomers of each compound in the chiral chromatographic analysis.
After elution from the SPE cartridges, the eluents will be evaporated slowly under
nitrogen gas. The concentrated samples containing metolachlor will be analyzed by
GC/MS while the fractions containing the polar metabolites will be analyzed by HPLC;
both the GC and HPLC will be equipped with chiral columns. For GC/MS, a fused silica
column coated with tert-butyldimethylsilyl--cyclodextrin will be used; this column has
been shown to partially separate metolachlor isomers (13). Also, a nonbonded permethylated -cyclodextrin column will be tested to examine if enantiomeric separation
of metolachlor could be improved. For the HPLC analysis of the polar metabolites, two
columns will be examined. First, the silica-based chiral reversed-phase system with
cellulose carbamate will be used. This column was shown to partially resolve the parent
metolachlor (13), but its usefulness in separating the OXA and ESA compounds still
needs to be tested. The other HPLC set-up that will be tested will use a conventional
reversed-phase stationary phase and a chiral mobile-phase containing -cyclodextrin.
Our preliminary work using capillary zone electrophoresis (CZE) proved -cyclodextrin
to be an effective chiral selector for the separation of metolachlor oxanilic acids (see
Figure 5) (not included in excerpt). Although only partial separation of the metolachlor
OXA was achieved in CZE, we were able to show for the fi rst time (in combination with
NMR data) that metolachlor indeed exists as eight stable isomers (14). The additional
interaction offered by the stationary phase in HPLC may result in increased separation
efficiency.
Soil Degradation Study. A controlled degradation study will be conducted using
soil samples taken from a field that has not been exposed to metolachlor and from a
Writing the Experimental Approach Section
435
field that has been previously treated with metolachlor herbicide. The reason for taking
samples from two different sources is to investigate the effect of different microbial
populations on the stereoselectivity of metolachlor degradation. A sterilized soil sample
will serve as a control. The soil samples will be divided into two sets: one will be
treated with commercial formulation Dual® (racemic metolachlor herbicide formulation) and the other with Dual Magnum® (S-enriched herbicide formulation). Each set
will be conducted in duplicate, and each sample will receive an application rate of 500
µg of metolachlor per 200 g soil. The fortified oil samples will be incubated in Petri
dishes at 20–25 °C, and the soil moisture will be controlled. Samples (about 10 g)
will be taken periodically from the Petri dishes for analysis, the fi rst one immediately
after fortification and then after 3, 7, 15, 30, and 60 days. The soil samples will be
extracted and analyzed for the parent compound and the OXA and ESA metabolites.
Enantiomeric ratios (ER) of the parent metolachlor will be calculated based on the
peak areas of individual isomers and will be used to determine the stereoselectivity of
metolachlor degradation. In addition, the ER of metabolites will be monitored.
Numbers and Units
Use correct abbreviations for units (e.g., µg, g, °C, days) and include a space between the
number and its unit (e.g., 25 °C). (See appendix A and table 3.2.)
Exercise 13.2
Look back at excerpt 13A and complete the following tasks:
a. Aga addresses both prior accomplishments and preliminary results in this
excerpt. Describe both and state how they help to establish Aga’s research
expertise.
b. Substantiate or refute the following statement: The author presents a logical
progression of proposed experiments.
c. Find one example that illustrates how to do each of the following: (1) use an
abbreviation for the first time, (2) report a number with units, and (3) format
an in-line citation. Suggest rules for each convention.
d. Find one example that illustrates the appropriate use of the following: (1)
commas, (2) hyphens, (3) semicolons, and (4) colons. What rules are followed in each case?
e. Comment on the verb tense(s) used to describe previous work and proposed
work. Give an example of each.
436
The Research Proposal
Analyzing Organization
A move structure for the Experimental Approach section is shown in figure 13.1.
The section is organized around three key moves: (1) Share Prior Accomplishments,
(2) Share Preliminary Results, and (3) Describe Proposed Methodology. These
moves parallel the information requested in many RFPs. For example, the ACS
Analytical Chemistry Graduate Fellowship RFP (excerpt 11A) prompts applicants
to summarize work already accomplished (i.e., prior accomplishments and preliminary results) and to summarize work planned for the term of the fellowship
(i.e., proposed methodology). Similarly, the NSF CAREER award RFP (excerpt 11C)
requires applicants to provide a summary of prior research accomplishments and
an outline of the research plan, including the methods and procedures to be
used. The Experimental Approach section is often the most technical section of
the proposal.
Exercise 13.3
Consider the RFPs for two NSF program solicitations: the Faculty Early Career
Development (CAREER) award (excerpt 11C) and the Collaborative Research in
Chemistry (CRC) award (excerpt 11D) Explain how the moves in figure 13.1 are
addressed in these RFPs.
1. Share Prior Accomplishments
(establish expertise)
2. Share Preliminary (Promising) Results
(lay the conceptual groundwork)
3. Describe Proposed Methodology
Cite
relevant
works
For each research objective:
3.1 Remind reader of promising results
3.2 Describe procedures/instrumentation (in a logical order)
3.3 Anticipate obstacles
Repeat (as needed) for different research objectives
Figure 13.1 A visual representation of the suggested move structure for the Experimental Approach
section of the Project Description.
Writing the Experimental Approach Section
437
Table 13.1 Common level 1 headings for the Experimental Approach section.
EXPERIMENTAL APPROACH
PROPOSED METHODS
EXPERIMENTAL SECTION
PROPOSED RESEARCH PLAN
EXPERIMENTAL DESIGN
PROPOSED RESEARCH ACTIVITIES
With the move structure for the Experimental Approach section in mind,
we are ready to analyze the moves and submoves in more detail. The entire section often begins with a level 1 heading. Common level 1 headings are shown
in table 13.1.
Move 1: Share Prior Accomplishments
The first move of the Experimental Approach section is to share prior accomplishments. The term “prior accomplishments” refers to completed works (e.g.,
published articles or otherwise disseminated results) and other accomplishments
(e.g., awards, collaborations) that are related to the proposed work. (Unrelated
accomplishments may be listed in a separate biographical statement but should not
be mentioned in the proposal.) The purpose of move 1 is to establish expertise and
convince reviewers that you have the necessary skills to complete the proposed
work. Move 1 usually begins at or near the start of the Experimental Approach
section. The length of move 1 varies with each proposal. Typically, the section is
longer for experienced researchers (i.e., those with prior grant support) because
they have more accomplishments to share. Move 1 is often demarked with a level
2 heading. Common level 2 headings for move 1 are shown in table 13.2.
Analyzing Excerpts
Let’s examine move 1 in authentic proposals. Perhaps the most direct way authors
share prior accomplishments is to cite their own published works. It is both appropriate and expected that authors call attention to their authored (or co-authored)
works, provided that they are related to the proposed work. Excerpts 13B–13D
illustrate this approach. Some authors, such as Lee and Lorigan (excerpts 13B
Table 13.2 Common level 2 headings for move 1 of the Experimental
Approach section.
438
Prior Accomplishments
Summary of Prior Accomplishments
Previous Work
Previous Accomplishments
The Research Proposal
and 13C), mention explicitly that their papers were published in the Journal of the
American Chemical Society. (Such journals as the Journal of the American Chemical
Society, Nature, and Science are particularly prestigious; hence, authors will often
mention them by name.) Other authors, such as Vyvyan (excerpt 13D), simply
include a citation to their own work. Either way, we encourage you to cite your
own works. The decision to include journal titles is up to you.
Excerpt 13B (Lee, 2001)
1. Nucleic Base Acidities. The N1 and N3 Acidities of Uracil. Published in J. Am
Chem. Soc. 2000, 122, 6258–6262. Our progress to date involves calculations and
experiments for the determination of nucleobase activities. We have learned that there
is an enormous difference in the inherent stabilities of anions at the N1 (7) and N3 (8)
positions in uracil (5a, Figure 1).
Excerpt 13C (Lorigan, 2002)
Logically, the first step for developing this method at lower magnetic fields (X-band
for EPR studies) is to fully characterize the bicelle system without the added complications induced by protein-lipid interaction. Over the last two years, we have accomplished this goal and published several articles describing our results (81, 86–88). The
first paper was published in J. Am. Chem. Soc. and demonstrates the effects of magnetic
phospholipids bilayer alignment by showing an EPR spectrum of a DMPC/DHPC/Yb3
“bicelle” sample doped with a cholestane spin label (81). . . . We followed up our initial
report with a second J. Am. Chem. Soc. paper that spectroscopically characterizes magnetically oriented phospholipid bilayers with EPR spectroscopy and discusses conditions
for optimal bicelle alignment at X-band (86).
Excerpt 13D (Vyvyan, 2001)
Our general approach to the synthesis of the heliannuols is illustrated by our recently
completed total synthesis of (±)-helliannuol D (4).19
A successful collaboration can also be mentioned as a prior accomplishment.
Collaborations strengthen expertise (two heads are better than one) and add to
the intellectual merit of a proposal by increasing the likelihood that the work will
be completed on schedule. Excerpts 13E and 13F showcase two ways that authors
describe collaborative relationships in their proposals.
Excerpt 13E (Aga, 2002)
Currently, the PI is collaborating with Prof. Bertold Hock’s laboratory at the Technical
University of Munich (TUM), Freising, Germany, to produce the antibodies against
isoxaflutole and its metabolites. Two rabbits have been immunized with different immunogens that were prepared by the PI at the University of Nebraska. Antibody production is being carried out at the TUM because they have the expertise and facilities for
Writing the Experimental Approach Section
439
polyclonal, monoclonal, and recombinant antibody production. Prof. Hock has agreed to
produce recombinant antibodies for isoxaflutole in the future for further immunoassay
development.
Farther vs. Further
Farther: more distant; at a greater distance
Further: additional; additionally
(See appendix A.)
Excerpt 13F (Kinsel, 1999)
In our initial studies, we have demonstrated, for the first time, that protein binding to
surfaces has a significant impact on subsequent protein MALDI MS ion signals. This
demonstration of principle was made possible through a number of important collaborations and student interactions between members of our research group and faculty in
the Department of Chemistry and the Biomedical Engineering Program at the University
of Texas at Arlington.
If you are at the start of your career, you may not yet have many prior accomplishments to share. In this case, you can establish expertise in move 2 (Share
Preliminary Results) instead. Excerpt 13G illustrates this approach. Here, Lyon
emphasizes what he has accomplished to date on the project, highlighting results
and relevant skills that he and his group have mastered. Do not hesitate to point
out, as Lyon does, that the results demonstrate your ability to perform tasks required
for your proposed work.
Excerpt 13G (Lyon, 2000)
Preliminary Results
Colloid Synthesis. Our group has investigated the synthesis of hydrogel particles
that can be derivatized covalently with proteins using standard aqueous cross-linking
procedures. . . . The first synthetic efforts have been focused on lightly cross-linked
( 1%) copolymers of N-isopropylacrylamide (NIPA) and acrylic (AA) or methacrylic
acid (MAA).51–53 These hydrogel spheres contain up to 95% water by volume, thereby
allowing for diffusion of molecules into the particle with only moderate steric inhibition.
The NIPA component of this material is thermoresponsive; poly-NIPA undergoes a fi rstorder volume phase transition at ∼32 °C.27,30 This phenomenon is evident from the data
presented in Figure 1. These are recently collected data from our group that demonstrate our ability to accurately measure polymer phase transitions via both turbidity and
photon correlation spectroscopy (PCS). Furthermore, the PCS data also demonstrate our
ability to measure the diameter of colloidal hydrogels in situ, without the use of invasive
electron or probe microscopies.
440
The Research Proposal
Phenomenon/Phenomena
Phenomenon (singular)
Phenomena (plural)
(See appendix A for other plural and singular scientific words.)
Exercise 13.4
Refer back to the proposal in excerpt 11A written in response to the ACS Analytical
Chemistry Graduate Fellowship. How does Amanda Haes, a graduate student at
the time, establish her expertise?
Exercise 13.5
We include another excerpt from Lyon’s proposal (excerpt 13H). In this excerpt,
Lyon is responding directly to the CAREER prompt to “include a summary of
prior research . . . accomplishments.” To respond to the prompt, he uses a chronological approach to describe his undergraduate, graduate, and postdoctoral experiences. What do you notice about his use of the third person (i.e., the PI) and the
first person (i.e., I) when referring to himself?
Excerpt 13H (Lyon, 2000)
Summary of Prior Research Accomplishments
The PI has extensive and broad experience in inorganic, analytical, physical, and
materials chemistry and has employed surface plasmon resonance spectroscopy (SPR),
electrochemistry, transient absorbance spectroscopy, spectroelectrochemical quartz
crystal microgravimetry, and photon correlation spectroscopy to the study of a wide
range of nanostructured materials and colloidal systems. The PI has also investigated
charge transfer in molecular and inorganic polymer systems using spectroscopic and
electrochemical probes.103–105 The PI’s research experience began as an undergraduate in
the lab of Professor Stephan S. Isied (1988–1992), where he synthesized small peptidic
mimics of zinc-binding protein active sites. . . .
Under the advisement of PhD mentor Professor Joseph T. Hupp, the PI successfully
used spectroelectrochemical quartz crystal microgravimetry to elucidate the mechanism
of charge transport . . . for both aqueous and nonaqueous sytems.106,107 This was the first
demonstration of proton-coupled electron transfer at oxide semiconductor interfaces.
These findings were then successfully applied to a new interpretation of photoinduced
electron transfer at similar interfaces, which are of importance in the field of solar energy
conversion.108 . . .
Writing the Experimental Approach Section
441
As a postdoctoral associate with Professor Michael J. Natan, the PI investigated plasmon coupling between noble metal films and metal colloidal particles using SPR in both
scanning and imaging mode. It was discovered that SPR signals due to protein-protein
interactions can be amplified ∼100-fold through. . . . 1,2 This work eventually evolved into
a particle-enhanced SPR immunoassay,2 which is currently in commercial development.
Also, as a part of this work, the PI designed and constructed an imaging SPR instrument for use in particle-enhanced high-throughput screening of combinatorial drug
libraries.109
The PI has recently moved on to investigations of colloidal polymer systems. . . .
Analyzing Writing
Before we conclude our discussion of move 1, we call your attention to the pointers near selected excerpts above. These sidebars and excerpts together highlight
correct usages of the following words, punctuation, or other writing features:
■
numbers and units (excerpt 13A)
■
farther vs. further (excerpt 13E)
■
phenomenon/phenomena and other singular/plural words (excerpt 13G)
To test your knowledge of these features, complete exercise 13.6.
Exercise 13.6
Find and correct the mistakes in the following sentences, or indicate that the
sentence is “correct as written”.
a. To further develop the chemosensor design, we will focus on chelation-enhanced fluorescence.
b. We expect samples sizes to be about 100 g.
c. The expected phenomena was observed only in the single spectra collected at
300 K.
d. We will extend the synthesis farther than previous works.
We end this section by examining a few commonly used verb tense–voice combinations in move 1. As shown in table 13.3, prior accomplishments are typically
written in active voice in either past tense or present perfect. Statements that
establish expertise are typically written in present tense.
442
The Research Proposal
Table 13.3 Common functions of different verb tense–voice combinations in move 1 of the Experimental
Approach section.
Function
Tense–Voice
Combination
Example
To highlight prior
accomplishments
Past–active
In previous work, we demonstrated that . . .
Present perfect–
active
We have completed a previous study that . . .
Present–active
The data demonstrate our ability to measure . . .
Present–passive
Our general approach is illustrated by our recently
completed total synthesis of . . .
To establish expertise
Our previous efforts have focused on . . .
Exercise 13.7
Identify the verb tense–voice combination in each sentence. What function does
each sentence serve? Consult table 13.3.
a. In prior studies, we demonstrated that protein binding to surfaces has a significant impact on . . . ion signals. (Adapted from Kinsel, 1999)
b. In 2007, we provided the first example of a Lewis acid promoted C-C bond
heterolysis of epoxides. (Adapted from Johnson, 2003)
c. Our previous works have established our ability to construct multilayered films.
d. Our ability to construct multilayed films is evidenced by our previous works.
13A Writing on Your Own: Share Prior Accomplishments
Make a list of research accomplishments that you have acquired to date that will help you
with your proposed work (e.g., publications, conference presentations, collaborations,
work-related experiences, instrumental expertise, technical training).
Based on this list, write a one-paragraph description of your skills and research accomplishments to establish expertise in your proposal.
Move 2: Share Preliminary Results
The second move in the Experimental Approach section is to share preliminary
results. Preliminary results (unlike prior accomplishments) refer to results that
are not yet published or disseminated. They suggest to reviewers that you have
Writing the Experimental Approach Section
443
Table 13.4 Common level 2 headings for move 2
of the Experimental Approach section.
Preliminary Results
Current Work
Initial Findings
Work in Progress
tested a few of the key ideas in your proposed work. Without at least some empirical evidence that your ideas will succeed, your proposal is unlikely to be funded.
(Indeed, chemists often joke that proposals are only funded if 90% of the work
is already done!) Like move 1, move 2 is often demarked with a level 2 heading.
Some examples of level 2 headings are shown in table 13.4.
Analyzing Excerpts
Let’s examine move 2 in authentic proposals. As authors share preliminary
results, many authors also use move 2 to lay the conceptual groundwork for their
proposed work. To this end, full color, computer-generated graphics are often
included. Excerpts 13I and 13J illustrate this approach. In each case, the authors
use full-color illustrations to share preliminary findings (the color is not reproduced here). We first saw the use of computer-generated graphics in chapter 12,
to introduce fundamental concepts about the research area. They serve a similar
purpose here. High-quality graphics effectively illustrate scientific concepts and,
at the same time, attest to the author’s skill and expertise as a writer. The familiar
saying “a picture is worth a thousand words” is absolutely true in proposals.
Computer-Generated Graphics
Full-color, high-quality computer-generated graphics (drawings and illustrations) are
widely used in proposals to illustrate scientific concepts.
In excerpt 13I, Lyon describes his group’s progress in using hydrogels to fabricate thin films. As he shares his preliminary findings, he uses text and graphics to help readers better understand his plans to construct multilayered films.
In Figure 2, he uses a drawing to illustrate how anionic hydrogel particles are
attracted to an amine-coated surface. Three anionic hydrogels are taken up by
four amines, suggesting that a “complete monolayer” does not form. In Figure
3, he presents empirical evidence from atomic force microscopy (not included
here) to support this hypothesis. In Figure 4, he illustrates how a single surface
can be extended to multiple layers, formed by alternating layers of hydrogel particles (negatively charged) and poly-allylamines (positively charged). In Figure 5
444
The Research Proposal
(not included here), he shares preliminary results that show conclusively that he and
his group are able to construct multilayered nanoparticulate hydrogel films. After
reading this section, his reviewers are better prepared to understand his work and
are likely more convinced that it will succeed.
Exercise 13.8
Read excerpt 13I and answer these questions:
a. List two concepts that Lyon develops as he shares his preliminary results.
Consider text and graphics.
b. What are the two ways in which Lyon refers to figures in the text?
c. How are Figures 2 and 4 labeled? Are the captions above or below the figures?
Do Lyon’s formatting conventions support those endorsed in chapter 16?
d. Would excerpt 13I be as effective without the figures? Explain.
Excerpt 13I (Lyon, 2000)
Preliminary Results
Thin Film Fabrication. The acrylic (AA) or methacrylic (MAA) acid portion of the
copolymer also offers a group that will interact electrostatically with amines—a convenient method for immobilization of polymers to surfaces.55–57 Figure 2 shows the general
methods; modification of a solid surface with the appropriate alkylamine renders the
surface amine-coated. Exposure of that surface to a suspension of carboxylated hydrogel
spheres results in surface immobilization of the particles by electrostatic attachment.
Figure 3 shows an atomic force microscopy (AFM) image of a representative hydrogelmodified surface recently prepared in our group. Due to interparticle repulsion, a complete monolayer is not formed under these conditions, resulting in a surface decorated
with well-defined particles.
Figure 2. Electrostatic adsorption of colloidal hydrogels to functionalized
surfaces.
Writing the Experimental Approach Section
445
This result suggests that polyelectrolyte multiplayer assembly methods can be
applied to these materials. These methods (developed by Lvov and Decher)58–60 allow for
the construction of stable, reproducible, submicron-think, polymer films by alternating
layer adsorption of polycations and polyanions from aqueous solutions. Accordingly,
we have begun investigating the feasibility of this multiplayer fi lm assembly method
using hydrogel particle or linear polyelectrolytes (poly-styrenesulfonate) as the anion
component and linear polyelectrolytes (poly-allylamine) as the cationic component in an
alternate-layer deposition process (Figure 4).
Figure 4. Layer-by-layer polyelectrolyte adsorption.
Figure 5 shows representative quartz crystal microgravimetry data recently collected
in our group for the deposition of just such a multilayer film. . . . Despite the need for
further investigation of the films, these data show conclusively that we are able to construct multilayered nanoparticulate hydrogel films via simple solution-based assembly
methods. Films prepared in this fashion are currently being characterized with respect
to their thickness and morphology (via profilometry and atomic force microscopy),
porosity (voltammetry), viscoelasticity (crystal impedance), refractive index (surface
plasmon resonance), and molecular structure (FTIR spectroscopy). These studies are
elaborated upon in the research methodology.
Figures and Captions
See chapter 16.
446
The Research Proposal
Data/Datum
Data (plural)
Datum (singular, rarely used)
(See appendix A for other plural and singular scientific words.)
Excerpt 13J also involves the preparation of thin films at molecular-length scales
but uses strategies of crystal engineering. Patrick proposes to investigate thin film
growth on substrates submersed in a liquid crystal (LC) solvent/solute mixture under
the influence of an external magnetic field. For example, in a preliminary experiment,
they deposited a fatty acid (tetracosanoic acid) from an LC solvent onto a graphite substrate. In the presence of a magnetic field, the deposited film was uniformly oriented
(crystalline); in the absence of the field, a randomly oriented (polycrystalline) film was
observed. Patrick includes an illustration to depict these phenomena. By combining
both text and illustration, Patrick presents his preliminary results in a way that establishes a clear conceptual framework for his proposed work.
Excerpt 13J (Patrick, 2000)
Summary of Preliminary Results
We have conducted preliminary investigations to assess the way LC solvents influence film formation in monolayers of small organic molecules on highly oriented pyrolytic
graphite (HOPG) substrates. A number of different molecular solute/
LC solvent combinations have been
investigated over the last year. In
most cases, samples were prepared
by deeply immersing a graphite
substrate into a reservoir of the LC/
solute mixture at ∼100 °C, then
allowing the system to gradually cool
to room temperature (Fig. 3). . . . The
reservoir was located in a magnetic
field, oriented with the field axis in
the plane of the substrate surface.
After preparation, samples were
removed and analyzed with scanning tunneling microscopy (STM).
The STM tip penetrated through the
thick LC solution to image molecules
in the monolayer at the graphite
interface. Results from three representative systems are summarized in
Figure 3. Preparation of oriented films.
Table 1.
Writing the Experimental Approach Section
447
Exercise 13.9
Cover up the figure in excerpt 13J and complete the following tasks:
a. Read the excerpt (without looking at the figure).
b. Based solely on the text, try drawing a sketch on your own that illustrates the
effect of the magnetic field.
c. Then look at the figure. How close were you?
d. In what ways did Patrick’s illustration help you gain a better grasp of the
proposed work?
e. Note how the text “wraps” around the figure in Excerpt 13J. In many
instances, authors also “box” their figures. Explain why these practices are
common in proposals but not in manuscripts submitted for publication.
Many authors use the word promising when sharing preliminary results, presumably because the word suggests that the proposed work will likely succeed.
For example, 10 of the 22 CAREER proposals cited in this textbook included the
word promising (and even very promising) in this move. Here are a few examples to
give you an idea of how the word was incorporated:
The extension appears to be
promising . . .
(From Johnson, 2003)
The results . . . were very
promising . . .
(From Aga, 2002)
Employing a particularly
promising class of . . . ligands
(From Warren, 2002)
Our efforts . . . are very
promising.
(From Vyvyan, 2001)
Upon identification of
promising leads . . .
(From Johnson, 2003)
promising . . .
(From Walker, 2001)
promising.
(From Sanov, 2002)
promising candidates . . .
(From Patrick, 2000)
A
promising new technique . . .
(From Lorigan, 2002)
A
promising lead structure . . .
(From Finney, 1999)
Early results are
(make) imaging . . . ions very
. . . (are)
The first entry in Table 1 represents the simplest implementation of the LCI
method, in which the LC solvent and solute building block were identical. Because
it is the simplest and best understood system studied so far, we will describe our
results for 8CB in most detail. We wish to emphasize, however, that LCI is not
restricted to 8CB; we have demonstrated it in other systems as well, including
systems in which the building blocks differed from the LC solvent and were nonmesogens.
448
The Research Proposal
The word recently (or recent) is also common in move 2. The ACS Style Guide
advises against using recently in journal articles (in part, because recently loses
its meaning so shortly after a paper is published), but its use is less objectionable in research proposals, which are short-lived documents. Investigators like
the word because it conjures up the image of a research group actively engaged
in the proposed work. A few examples of how recently is used in move 2 are as
follows:
recent NMR data reveal . . .
(From Lee, 2001)
recently prepared . . .
(From Warren, 2002)
Our
recently established methodology . . .
(From Lee, 2001)
Our
recently completed total synthesis . . .
(From Vyvyan, 2001)
...
recently collected data from our group.
(From Lyon, 2000)
Furthermore,
We have
Excerpt 13K illustrates how promising and recently are used in a complete paragraph. The author also uses the phrase “the first evidence of ____”. The word first
in this context is also common in move 2 because it underscores the originality of
preliminary findings. Empirical evidence for the author’s claims is provided in a
figure. Note that the author uses a slightly reduced font size in the figure caption.
This practice is sometimes allowed in proposals if space is tight.
Solvatochromism
Solvatochromism refers to changes in the electronic state of the solute (specifically, the
solute’s electronic state transition energy) caused by the solvent.
Excerpt 13K (Walker, 2001)
Early results are promising. We have recently completed a preliminary study that
examined the solvatochromic behavior of 4-aminobenzophenone (4ABP) adsorbed to
hydrophilic substrates from a variety of solvents. Hydrophilic substrates are polished
quartz surfaces that demonstrate complete wetting when exposed to water. . . . Figure
5a shows the SHG spectrum of 4ABP adsorbed to a hydrophilic interface from cyclohexane. . . . To our knowledge, these data represent the first evidence of surface-induced
solvatochromism at solid-liquid interfaces. Superimposed are UV–vis spectra of 4ABP
in bulk cyclohexane and bulk diethyl-ether. As anticipated, data show that the hydrophilic, silanol terminated surface renders the interactial environment more polar than
bulk cyclohexane.
Writing the Experimental Approach Section
449
Figure 5a. UV–vis and SHG spectra of 4ABP. The two UV–vis spectra are for 4ABP
in cyclohexane (open circles) and diethyl ether (open triangles). The SHG spectrum
(filled diamonds) shows solvatochromic shift of 4ABP adsorbed to the interface
between hydrophilic quartz and a cyclohexane solution.
Text Boxes, Wrapping, and Captions
Graphics in proposals are sometimes “boxed”. In some cases, the text is wrapped around
the graphic. To save space, slightly smaller font is sometimes allowed for figure captions.
Exercise 13.10
Read excerpt 13L and answer the following questions:
a. What words or phrases are used to emphasize that the preliminary results
are both promising and original?
b. Note that Johnson describes the results of his synthesis in present tense (e.g.,
the thermal reaction gives a diastereomer ratio . . . ) rather than in past tense
(e.g., the thermal reaction gave a diastereomer ratio . . . ). Suggest a reason for
this choice.
c. Find instances of past tense. For what purpose(s) does Johnson use past
tense?
d. Find examples of present perfect. For what purpose(s) does Johnson use
present perfect? (See table 6.2 for more on present perfect construction.)
450
The Research Proposal
Excerpt 13L (Johnson, 2003)
Our preliminary experiments have provided the first example of Lewis acid promoted
C-C bond heterolysis of epoxides and productive cycloaddition (eq 7). Under the influence of TiCl4·(THF)2 (2 equiv), epoxide 26 reacts with methyl pyruvate to provide acetal
27 (52% isolated yield), along with C-O cleavage product 28 (23 ºC, 3 h). The diastereoselectivity for formation of 27 is 2.3:1. We have performed the analogous reaction in
the absence of a Lewis acid; the thermal reaction requires several days at 110 ºC and gives
a diastereomer ratio (dr) of ca. 1.3:1 . . . Although not optimized from the standpoint of
chemoselectivity, these results are promising because of the relatively low reaction temperature and potential for enhanced diastereocontrol.
While vs. Although
While (during the time that)
Although (even though)
(See appendix A.)
Exercise 13.11
Reexamine excerpts 13K and13L for ways in which authors share preliminary
results in their proposals, and answer the following questions:
a. How much detail do the authors include in their preliminary results? What
details are included?
b. Count the uses of we and our in these excerpts. Why do you think it is so
common for authors to refer to themselves in move 2?
Analyzing Writing
Before we conclude our discussion of move 2, we call your attention to the pointers near selected excerpts above. These pointers and excerpts together highlight
correct usages of the following words, punctuation, or other writing features:
■
figures and captions (excerpt 13I)
■
data/datum (excerpt 13I)
■
while vs. although (excerpt 13L)
To test your knowledge of some of these features, complete exercise 13.12.
Writing the Experimental Approach Section
451
Exercise 13.12
Find and correct the mistakes in the following sentences, or indicate that the
sentence is “correct as written”.
a. While it is clear that the first three reactions were solvent dependent, this
may not be true for the next set of reactions.
b. The data clearly shows the expected relationship between time and
temperature.
c. Although the word recently is discouraged in journal articles, it can be used
in research proposals.
We end this section by examining a few commonly used verb tense–voice combinations in move 2 (table 13.5). Present perfect is commonly used to describe
preliminary work (done in the past); present tense is commonly used to share
preliminary findings (believed to be true over time). Active voice is also common.
Note that because authors want to call attention to their own promising results in
this move, personal pronouns such as we or our are often used.
Table 13.5 Common functions of different verb tense–voice combinations in move 2 of the Experimental
Approach section.
Function
Tense–Voice
Combination
Example
To describe preliminary
work (done in the past)
Present perfect–
active
We have recently completed . . .
Past–passive
Films were prepared by . . .
We have conducted preliminary investigations
to assess . . .
Samples were analyzed by . . .
To share preliminary
findings (that will likely
be true over time)
Present–active
Our preliminary results demonstrate that . . .
To our knowledge, these data represent the first
evidence of . . .
Under the influence of TiCl4(THF)2 (2 equiv),
epoxide 26 reacts with methyl pyruvate
to . . . (From Johnson, 2003)
To refer to graphics (e.g.,
figures or illustrations)
452
Present–active
Figure 2 shows the general method.
Present–passive
Results from three representative systems
are summarized in Table 1.
The Research Proposal
Exercise 13.13
Consider the following sentences used to describe preliminary results. Which are
written in active voice? Which are written in passive voice? Convert the sentences
that are written in passive voice to active voice to place greater emphasis on the
scientist/researcher.
a. A number of different molecular solute/LC solvent combinations have been
investigated over the last year. (From Patrick, 2000)
b. In most cases, we prepared samples by deeply immersing a graphite
substrate into a reservoir of the LC/solute mixture at ∼100 °C. (From
Patrick, 2000)
c. Our group has investigated the synthesis of hydrogel particles that can be
derivatized covalently with proteins using standard aqueous crosslinking
procedures. (From Lyon, 2000)
d. The first synthetic efforts have been focused on lightly crosslinked ( 1%)
copolymers of NIPA and acrylic (AA) or methacrylic acid (MAA).51–53
(From Lyon, 2000)
Exercise 13.14
Consider the following sentences that describe preliminary results (adapted from
Gudmundsdottir, 2001). For each sentence, choose the most appropriate verb
form. Be prepared to explain your choices.
a. The IR spectra of 1a before and after irradiation in an argon matrix is/was/are/
were shown in Figure 8.
b. The transient spectrum of azide 1h is/was/are/were taken immediately after
the laser pulse over a 200 ns time window.
c. The difference spectrum in Figure 7 has/had/have a strong band between 270
and 320 nm.
d. As the temperature is/was lowered, more of compounds 4a, 8a, and 9a are/
were formed.
13B Writing on Your Own: Share Preliminary Results
Decide what preliminary (and promising) results you will highlight to convince your readers
that your proposed work is feasible. For example, perhaps you have already collected your
samples, conducted calibration experiments, or tested your instrument under background
conditions. Decide if you need figures or tables to present the preliminary data or if they
can be adequately reported in the text.
Writing the Experimental Approach Section
453
Write one to three paragraphs to share these results. If possible, share the results in such
a way that builds a conceptual framework for your proposed work. If appropriate, include
computer-generated illustrations to elucidate these concepts.
Move 3: Describe Proposed Methodology
In the third (and last) move of the Experimental Approach section, you describe
how you will conduct your proposed work. A well-organized and logical progression of ideas is essential in this move. Most authors demark the start of this move
with a level 2 heading, parallel to the level 2 headings used for moves 1 and 2. A
few examples are shown in table 13.6.
As shown in figure 13.1, move 3 includes three submoves: remind reader of
promising results, describe procedures/instrumentation, and anticipate obstacles.
These submoves are typically accomplished in sequential order, and the sequence
is reiterated for projects with more than one research objective. A level 3 heading is commonly used to demark each new objective; it may be generic (e.g.,
Objective 1, Objective 2) or descriptive (e.g., Quantification of Surface-Protein
Binding Affinity). The language used in these level 3 headings should be parallel.
Consider the parallelism in the following examples from Lyon (2000):
Bioconjugate Synthesis—Stage 1. As described above, we have already demonstrated our ability to produce thermoresponsive copolymer hydrogel particles that possess groups for protein attachment.
Bioconjugate Synthesis—Stage 2. The second stage of the bioconjugate project will
involve more complex polymer structures and more challenging biological targets.
Parallelism
Headings should be parallel and begin with the same form of speech. (See appendix A.)
Table 13.6 Common level 2 headings for move 3 of the
Experimental Approach section.
454
Proposed Methods
Proposed Studies
Proposed Research
Proposed Work
Research Plan
Experimental Plan
The Research Proposal
It is important that the proposed work for each research objective be presented
in a logical order. Often, the section begins with lower risk experiments and
moves progressively toward higher risk experiments. Ordinal language (e.g., first,
second, last) is common and is used to reinforce a logical progression of ideas.
(Note: The convention of using ordinal language in the research proposal is quite
different from the journal article, where ordinal language is discouraged.)
Analyzing Excerpts
With that brief background in mind, let’s examine how authors accomplish
move 3 in authentic research proposals. Submove 3.1 (remind reader of promising results) serves as a transition between move 2 (Share Preliminary Results)
and move 3 (Describe Proposed Methodology). Ideally, submove 3.1 is accomplished in a sentence or two at the start of each research objective. You want
to remind the reader what you have already learned and then move on to the
proposed work. Five examples are shown below (P1–P5). Each passage begins
with a level 3 heading, to demark the start of a new objective. The text begins
by referring to a preliminary fi nding and then shifts to the proposed work; the
preliminary fi nding serves as the first step in a clear progression of planned
experiments.
P1 2A. IR studies of N15 labeled azide 1a. We are concerned with
providing further evidence that nitrene 2a was formed upon the
photolysis of azide 1a. To this end, we plan to synthesize azide 1a as
an N15 isotope labeled in the N1 position (see Figure 15), obtain IR
spectra before and after irradiation in an argon matrix, and compare the
calculated shift for the C-N15 band in nitrene 2a with the experimental
value. Because isotope shifts in IR bands can be calculated very
accurately, this will be an excellent proof of the formation of a nitrene
intermediate. (From Gudmundsdottir, 2001)
P2 1.1. Measurement of multiple acidic sites in thymine. Because we have
already embarked on the study of uracil (see Preliminary Results), we
will begin with thymine (4a, Figure 1), which is the 5-methyl-derivative
of uracil. (From Lee, 2001)
P3 Bioconjugate Synthesis—Stage 1. As described above, we have already
demonstrated our ability to produce thermoresponsive copolymer
hydrogel particles that possess groups for protein attachment. These
syntheses will continue, with the goal of producing gels across a range
of NIPA/AA copolymer ratios (protein attachment points). (From Lyon,
2000)
P4 Heliannuols A, D, and K. Our preliminary results show that the
biomimetic phenol epoxide cyclization route is valid for the exo
cyclization products such as heliannuol D (4), and we are hopeful that
Writing the Experimental Approach Section
455
the planned acid-catalyzed cyclization of epoxides like 21 will produce
endo products like heliannuol A (1). (From Vyvyan, 2001)
P5 Effect of Sample Preparation Protocol. Our preliminary studies
strongly suggest that there is an inverse relationship between the MALDI
ion signals observed for surface adsorbed proteins and the affinity of the
surface for binding those proteins. Although this relationship appears to
be well demonstrated above, numerous questions remain to be answered
about this approach. For example, how does the sample preparation
protocol impact the observed inverse relationship? In the first group of
experiments, we will vary the order of sample and matrix deposition
to determine if other sample preparation protocols lead to similar
observations. (From Kinsel, 1999)
Irradiation vs. Radiation
Irradiation (n.) is the act of applying radiation (n.).
Exercise 13.15
Reread P1–P5 and complete the following tasks:
a. Identify the preliminary findings and the proposed work in each example.
b. How common is it for authors to incorporate a graphic (i.e., table or figure)
into this submove?
c. How common is it for authors to cite relevant works in this submove?
d. How common is it for authors to use personal pronouns (we, our, I, and my) in
this submove?
Exercise 13.16
Aga (2002) presents three research objectives in her proposal. One of these is
shown in excerpt 13A. A second objective involves modeling the transport behavior of nitrates and antibiotics in the Central Platte watershed using the ArcView
geographical information system (GIS) and the EPA software package BASINS.
Given the following information (adapted from Aga’s proposal), complete submove 3.1 for her second research objective. Include a level 3 heading, and write
at least two sentences that transition from preliminary results to the proposed
work.
■
456
Assume as preliminary work, Aga has already built the project file using the
BASINS software (i.e., she has input data related to watershed topography,
point source discharges, flow rates, and property boundaries).
The Research Proposal
■
She proposes to use these data to simulate the transport rates of nitrates and
antibiotics from cattle and swine feedlot runoff into nearby waterways (primary, secondary, and tertiary streams).
■
Samples will be collected at least once a month at the feedlots and in the
nearby streams.
■
The measured feedlot concentrations of nitrates and antibiotics will be imported
into BASINS. Using these input values, BASINS will model the transport rates
and final concentrations of nitrates and antibiotics in the nearby streams.
■
Modeled results will be compared with experimental values.
After the transition from preliminary results to proposed work has been accomplished, you are ready to describe the procedures and instrumentation that will
be used in the proposed work (submove 3.2). In essence, submove 3.2 offers a
road map of the procedures to be followed. There are two conventional ways to
organize this road map. The first approach presents the work chronologically,
beginning with more straightforward and familiar experiments and then moving
toward more challenging and unexplored methodologies. The second approach
organizes the work according to underlying themes or desired outcomes. The
first approach is preferred when experiments build on one another and need to
be performed sequentially. The second approach can be used when the proposed
methods are largely independent of each other. Of course, combinations of the
two approaches are also possible.
Road Map for Proposed Work
Work plans can be organized (1) sequentially, (2) by underlying themes or desired outcomes, or (3) by combining the two approaches.
We start with examples of the sequential approach. With this approach, you
begin with more routine experiments, ones that are reasonably likely to succeed
(e.g., calibration or optimization procedures). The initial set of experiments can
also serve as a test case and/or show that you can reproduce literature values. For
example, Aga (P6) proposes first to explore conditions that will optimize immunoassay sensitivity, and Spain (P7) proposes to begin with a study of topography,
using published methods and a self-assembled monolayer with a known structure.
Literature Values
Values reported in refereed publications.
Writing the Experimental Approach Section
457
P6 First, several parameters will be explored to determine the optimum
conditions at which the immunoassay will have highest sensitivity for
the target analytes. These parameters will include various preparations
of hapten-enzyme conjugates, varying strengths of assay buffers, varying
incubation times, and two signal-amplification techniques using avidinor streptavidin-biotin complexes. (From Aga, 2002)
P7 We will begin with a study of the topography of an n-alkanethiol
self-assembled monolayer (SAM) anchored to a Au(111) substrate.
Alkanethiols will be attached to a Au(111) substate by published
methods.44 The SAM will be imaged by atomic force microscopy (AFM)
to assure that the known structure is observed.45 (From Spain, 1997)
Of course, a successful proposal must also forge ahead into less familiar territory.
It is not enough to conduct the “easy” experiments; you must approach the “cutting edge” or forefront of your field. For this reason, Aga goes on to describe how
the optimized immunoassay will eventually be used to test for analytes in more
complex environmental samples, and Spain proposes a sequence of experiments
that will culminate in the deposition of translationally “hot” metal atoms on a
self-assembled monolayer system. The important point in these examples is how
authors develop a clear and logical order for their proposed work.
A similar approach is used by Lyon (excerpt 13M). He divides his proposed
methods into two stages; the second stage is described as more complex and challenging than the first. In his description, fewer specific details are included in
stage 2 (e.g., stage 1 cites a specific synthetic procedure, whereas stage 2 refers to
more general coupling chemistries). The lack of specificity in stage 2 is acceptable
because of the difficulties associated with predicting specific approaches as you
project your work farther into the future.
Excerpt 13M (Lyon, 2000)
Bioconjugate Synthesis—Stage 1. As described above, we have already demonstrated our ability to produce thermoresponsive copolymer hydrogel particles that
possess groups for protein attachment. These syntheses will continue, with the goal
of producing gels across a range of NIPA/AA copolymer ratios (protein attachment
points). . . .
The bioresponsivity of the hydrogel conjugates will initially be investigated with
simple protein-protein and protein-ligand pairs where one of the binding partners will
be covalently attached to the hydrogel. . . . First, we will use carboiimide coupling methods54 to covalently attach one of the binding partners to the carboxylate moieties in the
hydrogel. Specifically, we will . . . [goes on to describe more specific methods].
Bioconjugate Synthesis—Stage 2. The second stage of the bioconjugate project
will involve more complex polymer structures and more challenging biological targets.
First, we will explore factors such as protein loading, particle size, polymer crosslinking density, and copolymer ratio/identity in a highly parallel fashion to evaluate the
biosensitivity of a wide range of hydrogel bioconjugates. This will allow us to rapidly
458
The Research Proposal
converge upon a highly optimized polymer-protein conjugate based on NIPA hydrogels.
Second, we will expand our approach to other coupling chemistries (e.g., maleimide,
biotin-streptavidin, photo-crosslinking). By broadening the range of chemistries available, these colloidal bioconjugates will have wider applicability to other biochemistries
and film fabrication methods. We will also begin to explore other biological interactions
such as ligand-receptor binding, DNA hybridization, enzyme-substrate interactions, or
protein-DNA complexation to further evaluate the generality of our approach.
The sequential approach is also common in proposals written by synthetic
chemists (a multistep synthesis is inherently step by step). Vyvyan (excerpt 13N),
for example, proposes a strategy to synthesize a select group of heliannuols (alleopathic natural products isolated from the sunflower) in an optically pure form.
One approach that he will explore involves enantioselective cross-coupling reactions between an alkyl zinc reagent and an aryl bromide. He begins with experiments that will utilize recently developed catalysts and produce products with
known optical rotation data. Subsequent reactions are described that will lead
potentially to the desired stereospecific heliannuols A and D.
Excerpt 13N (Vyvyan, 2001)
Asymmetric Cross-Coupling Reactions. An attractive method to attach the side
chain and establish the benzylic stereocenter of our target compounds is an enantioselective cross-coupling of an alkyl zinc reagent and an aryl bromide. . . . Our approach will
examine the reaction of secondary alkyl zinc species (e.g., 30) with aryl halides (e.g., 31
and 4-bromotoluene) using chiral catalysts such as 45 and 46. Simpler routes by which
to prepare prospective chiral ferrocene-based catalysts have recently been developed,
which bodes well for the future development of this process.40 Chiral GC or HPLC and
optical rotation data of the products will be compared to literature values for curcuhydroquinone 33 and curcumene 47, respectively, to determine the sense and level of
enantioselectivity (Scheme 6).28,38a,41
Once this process is explored with the model system to assess the level of enantioselectivity, we will then prepare alkyl zinc reagent 48 from 44 using standard
methods22,36,42 and cross couple 48 to aryl bromide 18 using the appropriate chiral
catalysts (Scheme 7). Although the acetonide stereocenter in 48 is somewhat remote
from the coupling site, the stereocenter may serve to enhance the stereoselectivity of the
cross-coupling process because the two possible products are diastereomers, not simply
enantiomers. This reaction will produce 49 from (S)-48 and 50 from (R)-48 that can
then be converted to epoxides 51 and 52 using standard methods.43 Epoxide 51 leads to
heliannuol D 4 after base-promoted epoxide cyclization and deprotonation. Similarly,
epoxide 52 leads to heliannuol A 1 after acid-promoted cyclization.
Respectively
See appendix A.
Writing the Experimental Approach Section
459
(S) and (R)
Use italic (not bolded) type for prefixes like (S) and (R) that denote stereochemistry.
(See chapter 4.)
The last example of a sequential approach is from Sanov (excerpt 13O). A
series of increasingly complex experiments is proposed to study the photochemistry of O2, S2, and OCS. Sanov begins with the “easier” diatomic anions (O2
and S2–), which will serve as prototypes for subsequent experiments. Next, he
will study a larger, polyatomic anion (OCS) and its cluster ions, OCS(H2O)k.
In the future, he will study even larger dimers and trimers (OCS)n (n 2) and
their hydrated counterparts.
Excerpt 13O (Sanov, 2002)
Electronic Structure via Photoelectron Imaging. . . . Initial experiments will focus
on O2 and S2. . . . Besides their importance, O2 and S2 will serve as prototype systems for developing the photoelectron imaging approach and . . .
The (OCS)2 anion is the next logical system, taking us into the realm of polyatomic
anions with rich photochemistry and more complex symmetry. (OCS)2 is an example
of how dramatically the properties of a compound (e.g., carbonyl sulfide) may change
upon electron capture and/or solvation.138 . . .
Our next step will be to use “differential imaging” to study cluster chemistry and
examine the effects of solvation (hydration) on electronic structure. . . .
Building on the initial fi ndings described in Section 4, we will acquire photoelectron images of OCS (H 2O)k cluster anions at different wavelengths in the visible and
UV and investigate the dynamics of hydration and hydration-induced stabilization of
OCS . . . .
By examining the images of OCS (H 2O)k ions, we expect to attribute the
changes with k to the effects of hydration. . . . In the future, we plan to extend these
studies to (OCS) n (n 2) cluster anions and their hydrated counterparts [(OCS)n
(H 2O)k].
Affect vs. Effect
Effect (n.): a consequence, result
Affect (v.): to influence, change
(See excerpt 13U for the proper use of affect. See also appendix A.)
460
The Research Proposal
Exercise 13.17
Dyer (2001), in his CAREER proposal, proposes six key experiments to evaluate
polar order and polar stability of organic self-assembled monolayers. A gold-coated
surface will be partitioned into two surfaces, allowing two different hydrogenbonding moieties to be studied simultaneously. Dyer uses ordinal language (first,
second, third, fourth, fifth, and sixth) to make the sequence of experiments clear.
However, even without this language, the order is predictable because the experiments are arranged in order of increasing complexity.
We have listed the first three of the six experiments (a–c) below. Arrange them
in order of complexity (and, hence, the order in which they will be performed),
identifying the correct ordinal language (first, second, third) where indicated.
(SHG = second harmonic generation; SAM = self-assembled monolayer.)
a. First /Second/Third, the SHG signal will be measured when both surfaces
exhibit complementary H-bonding moieties. Ideally, we predict that the SHG
signal should be twice that of the (first, second, third) experiment because
both surfaces will contribute to the bulk polar orientation.
b. First /Second/Third, a control experiment will be performed . . . where the
terminal functionality on both surfaces is an alkane. . . . In this instance, the
SAM surface will not participate in H-bonding with the bulk liquid crystal
(LC) and therefore the bulk material will not exhibit polar order; thus, the
SHG signal should be very low.
c. First /Second/Third, the SHG signal will be measured when only one surface
has a hydrogen bonding SAM and the other surface is terminated with an
alkane. We expect the SHG signal to be significantly larger than for the first/
second/third experiment where both surfaces were terminated with alkanes.
Exercise 13.18
Below are five excerpts (a–e) adapted from the “Proposed Studies” section of
Kinsel’s (1999) CAREER proposal. However, the excerpts are out of order, and
we have omitted three words (first, next, and collectively) that were included in the
original proposal. Using language clues and figure 13.1 as guides, arrange these
excerpts in the correct order (1–5), and select the most appropriate missing word
where indicated.
a. First /Next/Collectively, the above studies should allow us to determine the
optimum sample preparation and MALDI conditions with which to characterize surface-protein interactions.
b. First /Next/Collectively, we will further extend our investigations to a broader
range of biomolecules and to a wider array of pulsed RF plasma polymer
Writing the Experimental Approach Section
461
modified surfaces. In these studies, the thrust of the research will be to
further define the range of systems for which the MALDI methodology can
be used to study surface-protein interactions. The selection of peptides and
proteins will include larger proteins commonly used in MALDI studies (e.g.,
ubiquitin, chicken egg lysozyme, horse apomyoglobin, trypsin) as well as
peptides and proteins that are readily radiolabeled (e.g., substance P, bovine
serum albumin).
c. For example, our preliminary MALDI MS studies employed a somewhat
unconventional sample preparation approach in which the protein deposition step preceded the matrix deposition step. (In the conventional approach,
the protein is co-deposited with the MALDI matrix solution.) . . . Thus, in
the first/next/collectively group of experiments, we will explore different
sample preparation methods to determine if other protocols also lead to an
inverse relationship between surface-protein binding affinity and the MALDI
ion signal.
d. These studies will be followed with experiments that examine the influence
of the matrix solvent on the inverse surface-protein binding affinity/MALDI
ion signal relationship.
e. Our preliminary work strongly suggests that there is an intimate relationship
between the MALDI ion signals for surface-adsorbed proteins and the affinity
of the surface for binding those proteins. Although this relationship appears
well demonstrated in the examples above, numerous questions remain to be
answered.
We now consider two examples of proposed methods that are not organized
sequentially. In excerpt 13P, Finney describes three near-term projects that will
be conducted simultaneously. He offers an overview to describe the three different areas and then goes on to give more details about each area (not included).
Ordinal language is still used, but in this case, it is used to convey the order in
which the projects will be presented, rather than the order in which the experiments will be conducted.
Excerpt 13P (Finney, 1999)
Proposed Near-Term (0–24 month) Research
Overview. The proposed near-term research is divided into three areas, which will
be pursued simultaneously. The first is the complete characterization of the current
mercury-responsive fluorescent chemosensor system, including the measurement of
fluorescence lifetimes, to discern the origin of the conformational control of fluorescence. The second is to develop two classes of substituted biaryl acetylenic fluorescent
chemosensors, to move the observed fluorescence into the visible region and increase
the magnitude of the fluorescence signal, which occurs upon conformational restriction.
462
The Research Proposal
The third is the construction of a 100-member combinatorial library of fluorescent
chemosensors related to the established mercury binder, to identify a combination of
recognition domains that will allow selective, high-affi nity detection of mercury in the
presence of other metal ions.
Which vs. That
Which signals extra information.
That signals essential information about the word or phrase that comes before it.
(See appendix A.)
A second example is shown in excerpt 13Q. Harpp’s proposed work initially
involves the collection of field data in two sampling campaigns. Following collection, the samples will be analyzed for trace and major element concentrations and
isotopic ratios. In her case, the order in which she conducts these analyses is less
important than how she will use the data to answer questions about plume-ridge
interaction mechanisms. Thus, she organizes her proposed work (titled “Proposed
Plan”) not by the tests she will perform, but rather by the types of information the
analyzed data will provide (i.e., information about formation mechanisms, melting dynamics, and spatial distributions).
Excerpt 13Q (Harpp, 1998)
Proposed Plan
To evaluate properly the plume-ridge interaction mechanisms described above, it is
essential that we establish a thorough database from those poorly sampled regions of the
northern Galápagos, Wolf, Darwin, and Genovesa Islands. We propose to carry out two
field excursions, one to Wolf and Darwin Islands, and a second to Genovesa, to map and
collect representative samples for geochemical analysis. All three islands remain essentially unmapped at this time. The geochemical data will then be examined in conjunction with the PLUM02 expedition data from Pinta Island (Cullen and McBirney, 1987;
White et al., 1993) and Marchena Island (Vicenzi et al., 1990) for extensive modeling of
mixing and melting parameters.
From each island, a suite of samples will be collected where the geologic relationships
are well established. This will be done via careful flow-by-flow mapping, assessment of
relative ages of flows, and paleomagnetic work to confirm correlation of field relationships.
Emphasis will be placed on obtaining as extensive a stratigraphic section as possible. The
samples will be examined for petrographic variations, trace element and major element
concentrations, and isotopic ratios. With these data, we will evaluate the following:
(1) Formation mechanisms. How are the northern Galápagos Islands and seamounts
related to the plume and the ridge? Is the WDL a channel to the ridge from the plume,
Writing the Experimental Approach Section
463
a leaky fault, or related to near-ridge volcanism? How is Genovesa related to the ridge,
and the adjacent islands of Pinta and Marchena? We will examine the geochemical
evolution of Wolf, Darwin, and Genovesa lavas to address these questions. . . .
(2) Melting dynamics and source composition. Rare earth inversion using the path
integral method of White et al. (1992; McKenzie and O’Nions, 1991) will be used to
quantify the melting parameters and approximate source compositions (e.g., Harpp,
1995; Mahoney et al., 1993). . . .
Rare earth element data will also serve as the basis for a forward modeling study to
better constrain melting systematics in the Galápagos. The melting model will invoke
clinopyroxene-rare earth element partition coefficients, which vary with composition
(Gallahan and Nielsen, 1992), and a polybaric or column melting process. . . .
Isotopic ratios will be used to constrain source compositions and the contributions
from the plume and ridge to the island lavas. Harpp (1995) showed that magma mixing
occurs at the source level, prior to melting. The forward melting model will be applied
to different proportions of plume and ridge compositions to reproduce trace element
REE systematics in the erupted lavas. From this process, both the original source
compositions as well as the range in melting conditions experienced by magma at each
site will be constrained. This information will assist in developing a map of the thermal
and compositional structure of the present-day Galápagos plume and its interaction
with the GSC.
(3) Spatial distribution of geochemical variations. Existing data from Marchena
and Pinta Islands, PLUM02 data from the WDL, and the new Wolf, Darwin, and
Genovesa data will be compiled into a comprehensive geochemical database for further
examination of the formation mechanisms described above. The spatial distribution of
geochemical variations relative to the plume and the ridge will be examined in detail.
Author–Date Citations
The author–date format is one of three common ways to cite others’ works. (See chapter 17.)
Exercise 13.19
Look back at excerpts 13P and 13Q and answer the following questions:
a. Which authors cite relevant works?
b. Based on these two excerpts, when do you think it is most appropriate to
include citations in submove 3.2 (describe procedures/instrumentation)?
Before we leave submove 3.2, we want to address one more question: how much
detail should be included when describing proposed methodology? In a journal
article, the general rule of thumb is to include enough detail so that an expert
in your field can repeat the experiment. Thus, a journal article Methods section
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The Research Proposal
would include details such as the names and locations of vendors, compound
purity, gram weights for reagents, operational parameters, reaction conditions
for a synthesis (time, temperature, solvent, etc.), and so on.
Operational Parameters
Unlike the methods section of a journal article, operational parameters (settings under
which an instrument is operated) are not typically included in the methods section of a
proposal. (See chapter 3.)
In a research proposal, however, such details are often omitted. This is true
for several reasons. First, a journal article needs sufficient detail to allow others
to repeat the work; a proposal needs only to convince your readers that you can
do the work. Second, proposals typically describe multiple experiments that will
culminate in numerous publications. You simply do not have enough space to
describe each experiment in detail. Third, you most likely do not yet know the
details for many of your proposed experiments, particularly those planned for
the distant future; hence, it is customary to describe your work in more general terms. Finally, too many details can obscure the underlying purpose of your
work. The emphasis should be on the general approach, not the minutiae; you do
not want to bury your readers in details that may distract them from the importance of your project.
A journal article needs sufficient detail to allow others to replicate the work; a proposal, on
the other hand, needs to convince your readers that you can do the work.
That said, let’s consider a few examples. We begin with excerpt 13R, which
includes a rather lengthy description of the proposed methods—but note that
the general approach, not the experimental details, is emphasized. The author
begins with a description of the general methods, focusing on the instrument
that will be used, a Fourier transform ion cyclotron resonance mass spectrometer (FTMS). If this were a journal article, one would expect to find a formal
description of the operational parameters, but instead Lee focuses on the novel
way in which the instrument will be used (for acidity bracketing). Because this
novel application is central to the success of the project, precious space is used
to describe the technique. In a logical order, she describes two types of experiments; the first type (bimolecular reactivity) is simpler than the second (acidity
bracketing). After explaining the general process of acidity bracketing, she goes
on to describe how this method will be used to measure the multiple acidic sites
in thymine. She mentions by name the reference acids that she will use, building
Writing the Experimental Approach Section
465
on her experience with uracil and strengthening the reader’s confidence that she
knows what she is doing. She briefly points out that the acids are commercially
available, but does not take valuable space to list potential vendors or compound
purity, information that would be included in a journal article.
Excerpt 13R (Lee, 2001)
Research Design and Methods
General Methods. The instrument that will be used to execute the gas-phase
experimental portion of the proposed research is a Finnigan 2001 dual-cell Fourier
transform ion cyclotron resonance mass spectrometer (FTMS or FTICR), equipped with
both electron impact (EI) and electrospray ionization (ESI). FTMS is a high-resolution,
high-sensitivity technique that allows the entrapment and detection of gas-phase
species.17,18 Gas-phase ions are trapped in a magnetic field, much like a reactant sits in a
flask in solution. The instrument is a mass spectrometer; therefore, we will often refer to
the mass-to-charge (m/z) ratio of ions, which is the method we use to identify species.
(M-1) – or (M-H) – refers to a molecule M that has been deprotonated; for example, H2O
has an (M-1) – ion of m/z 17 (HO –).
Herein, we describe two main types of experimental techniques that we will utilize
once the ion is trapped. First is simple bimolecular reactivity. An ion in the FTMS is
“trapped” between plates of a “cell.” One can introduce neutrals into that cell with which
the ion can react in a bimolecular fashion.17,18 The reactant and product ions can be
detected with the mass spectrometer, allowing one to obtain qualitative information (i.e.,
what products are formed) as well as quantitative information (kinetics and product distributions). We have a “dual cell” setup, which comprises two interconnecting reaction
regions. Ions can be transferred from one cell to another, but not neutrals. Therefore, if
one produces an ion in one cell, and wishes to isolate that ion from any neutrals present,
one can transfer that ion to the second cell.17,18
The second type of experiment is “acidity bracketing.” This technique is used to
measure the gas-phase acidity of a species of interest. In this technique, species of
known acidities are allowed to react with the anion of unknown acidity. The ability of
the anion of unknown acidity to deprotonate relatively stronger acids, and the inability
of the anion to deprotonate weaker acids (stronger bases), allow one to bracket the acidity of the unknown acid.19 We have also developed a new method for measuring multiple
acidic sites.3 To our knowledge, this is the first example of such measurement being
carried out in an FTMS.20 For example, uracil has two acidic sites, at the N1 and N3
positions. The N1 site is more acidic, so the N1– ion 7 is less reactive than the N3 – ion 8.
Under normal bracketing conditions, deprotonation by hydroxide produces both the
N3 – and the N1– ions, but the N3 – ion reacts with any neutral uracil present to deprotonate the N1-H and form the N1– ion. We call this neutral-catalyzed isomerization. Such
isomerization has also been observed between the monoenolate of acetic acid and the
acetate ion in a flowing afterglow apparatus.20
To bracket the N3 site, we must perform the deprotonation of uracil under conditions
that will allow the N3 – to be sustained; that is, we remove the N1– /N3 – mixture from the
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The Research Proposal
neutral uracil environment as quickly as possible. First, we allow hydroxide to deprotonate uracil, presumably at N1 and N3; then we immediately transfer the ions to our
second cell, which is free of uracil neutral. We then allow the M-1 of uracil (m/z 111) to
react with reference acids. In summary, by forming a mixture of ions deprotonated at the
less and more acidic sites, and isolating the ions from the neutral precursor by transfer
into the second cell, we avoid the neutral-catalyzed isomerization that results in loss of
the ions deprotonated at the less acidic site. This technique is utilized extensively in this
project. . . .
Measurement of multiple acidic sites in thymine. Because we have already
embarked on the study of uracil (see Preliminary Results), we will begin with thymine
(4a, Figure 1), which is the 5-methyl-derivative of uracil. Our calculations at B3LYP/6–
31 G* predict that the gas-phase acidities of thymine N1 and thymine N3 should be 331
and 343 kcal/mol, respectively. These values are in agreement with earlier calculations
by Zeegers-Huyskens et al.36
To bracket the N1 site of thymine, we will use dichloroacetic acid (Hacid = 328.4
kcal/mol), difluoroacetic acid (331.0), hydrochloric acid (333.3), pyruvic acid (333.5),
2-bromo-butyric acid (336.8), 2-chloropropionic acid (337.0), and trifluoro-m-cresol
(339.3). These acids have acidities in the range that should allow us to bracket the acidity
of the N1H of thymine. . . .
All these reference acids are commercially available liquids or gases; although some
of the liquids are not very volatile (for example, . . .
Hyphenated Two-Word Modifiers
Two words that together describe a noun are usually hyphenated, unless the first word
ends with –ly. (See appendix A.)
Comprise vs. Compose
See appendix A for more information on these commonly confused words.
Similarly, Aga (excerpt 13A) describes the types of columns that she will use
to achieve enantiomeric separation (an essential feature of her proposed work),
but she does not devote space to a description of GC/MS parameters (e.g., temperature program, carrier gas, flow rates). She describes the general approach that
she will use to analyze soil samples in the soil degradation study but provides
few details on how soil moisture will be controlled or how the soil samples will
be extracted and analyzed (details we would expect to see in a journal article
describing this work).
In excerpt 13S, Hergenrother, a combinatorial chemist, describes how he will
synthesize a chemical library of 6,000 compounds. The synthesis is illustrated in
Writing the Experimental Approach Section
467
a scheme (not included here) and described briefly in the text. To conserve space,
he refers to reactions by name when possible (e.g., a Grignard alkylation and
Horner–Emmons olefination) rather than describing the steps of the reaction
sequence. He refers to general steps that will be taken (e.g., oxidation, deprotection, protection, and acylation) but does not include details such as stoichiometry,
reaction times, and reaction temperatures. He concludes by suggesting that this
method could be expanded 10-fold to create a library of 60,000 members.
Excerpt 13S (Hergenrother, 2002)
The library will be synthesized as follows (Scheme 5): To the silyltrifl ated 500 µm
polystyrene beads will be attached 10 different heterocyclic alkenes to provide 1; the
synthesis of these alkenes will be described in the next section. After conversion of
the olefin to the aldehyde, the electrophilic functionality will be appended. Thus, the
beads will be split and the aldehyde will be subjected to three different types of reaction with 30 different building blocks: a Grignard alkylation followed by oxidation,
a Horner–Emmons olefination, and a zinc trifl ate-mediated alkyne addition followed
by oxidation.22 This process will provide a collection of 300 compounds containing
a ketone or a ,-unsaturated electrophile (Scheme 5, 2). The secondary alcohol will
then be deprotected and subjected to 20 acylating agents, producing 6,000 compounds.
Finally, deprotection of the carboxylic acid and simultaneous cleavage from the resin
will provide compounds with the aspartic acid sidechain (Scheme 5, 3). The carboxylic
acid will be protected as the tris(2,6-diphenylbenzyl)silyl ester, a protecting group that
is stable to Grignard reagents and other harsh conditions.23 Of course, if this protecting
group were to be a problem, the compounds would simply be protected as the alcohols
and then oxidized at a later stage. . . . Once the synthesis of this 6,000 member library is
successful, it could easily be expanded to 60,000 members.
Exercise 13.20
Consider the level of detail in excerpts 13T and 13U. What do the authors tell
you about their general approach? Do they include enough detail for you to repeat
their experiments? Propose an explanation for the amount of detail provided.
Excerpt 13T (Patrick, 2000)
General Methodology. Films will be prepared by deeply immersing substrates in a
liquid crystal (LC) solution (several mm) to ensure that no memory of anchoring at the
air-LC interface remains at the depth of the substrate.36 In general, solutions will be prepared to give the smallest concentration possible such that the solute undergoes preferential adsorption (see below). In some experiments, fi lms will be prepared in a magnetic
field, using a variable strength (up to 1.3 T) electromagnet. Solution properties will be
characterized in each case by separately measuring the bulk-phase anisotropic and mean
magnetic susceptibility of the mixture. These measurements will be performed using
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The Research Proposal
the Faraday–Curie method.37 Because solutes can alter the phase transition temperature of a LC, we will independently measure the phase transition temperature for each
solution by optical analysis using a polarizing microscope equipped with a temperaturecontrolled sample stage.
Since vs. Because
Use since to connote the passage of time; otherwise, use because. (See appendix A.)
Excerpt 13U (Spain, 1997)
Film topography as a function of the metal atom kinetic energy will be measured.
A beam of hyperthermal Au atoms will be directed onto the organic layer. If a polycrystalline film is obtained, as with the thermal Au atoms, we will use atomic force microscopy (AFM) to measure film morphology. With AFM, we will determine if the film is
smooth or rough (with steps) and if it is amorphous or polycrystalline. If a polycrystalline film is produced with both low and high kinetic energy particles, we will measure
the average size of the microcrystallites to see if larger grains are observed with the
higher energy species. . . . In this way, our studies will explore whether or not increased
Au atom energy can affect the grain size on amine-terminated surfaces.
Exercise 13.21
Reexamine excerpts 13R–13U and answer the following questions:
a. To what extent do the authors cite relevant works when describing their procedures and instrumentation?
b. For what purposes do the authors cite the primary literature (e.g., support
claims)? Provide at least one example for each purpose.
c. Which citation format seems to be most common: superscript numbers, italic
numbers in parentheses, or the author-date format?
d. Now glance back at excerpt 13Q. What citation format is used? Suggest a
reason for the differences in citation formatting.
The third submove of move 3 (anticipate obstacles) stems from the fact that
research proposals, to varying degrees, chart new territory. As with anything
new, there will be obstacles that must be overcome. You have learned this lesson
already if you have joined a research group. Unlike cookbook lab experiments,
where most of the “bugs” have been worked out, research is full of bugs. Moreover,
even well-established methods have limitations; indeed, one of the first lessons
that you learn in a research group is the limitations of your technique. Such limitations can be straightforward, such as an instrument’s detection limits, or more
Writing the Experimental Approach Section
469
subtle, such as a side reaction that competes unknowingly with the desired reaction mechanism. It is best to address these limitations directly in your proposal.
By doing so, it demonstrates that you have thought carefully about your project
and that you have sufficient experience to recognize what might go wrong.
Let’s examine how authors do this in their writing. Lyon (excerpt 13V) identifies potential pitfalls in his work (demarked by a level 3 heading). His anticipated
obstacle is that the thermoresponsive polymers may lack sufficient bioresponsivity. He points out the problem, and also includes a contingency plan, or possible solution to the problem. In his case, he will draw on a large array of more
complex responsive polymers, if the simpler ones do not work. Similarly, Lee
(excerpt 13W) reassures her readers that she will address potential complications caused by “hot” ions in her instrument by using argon to cool the ions and
will improve her ability to measure acidity of the less acidic site by using deuterated reference acids.
Contingency Plan
Plan to address unplanned events or obstacles. Effective research proposals anticipate
obstacles and include contingency plans to solve them.
Excerpt 13V (Lyon, 2000)
Potential Pitfalls. The major pitfall in this work concerns the ability to induce bioresponsivity in thermoresponsive polymers. It is conceivable that while some thermodynamic perturbations may occur, they may not be large enough for the material to be of
high utility or applicability. Fortunately, a tremendous array of more complex responsive
polymers has been described, which implement backbones other than those found in
the traditional NIPA gel (dextrans, carbohydrates, polyglycols, polystyrenes, polyamines,
etc.)24,29,32,45,100–102 These materials are often multiresponsive (temperature, pH, and/or
ionic strength) and display much more complicated phase transition behavior. Although
it would be unwise to use these materials in the early stages of the project due to their
complexity, we will quickly move to explore these materials as colloidal bioconjugates if
our initial choice of hydrogel proves to be unsuccessful. It is expected that we will learn
enough of how proteins modulate gel solvation thermodynamics from the early work
such that our choice of the second-generation hydrogel will be an educated, rational, and
successful one.
Excerpt 13W (Lee, 2001)
A few caveats should be mentioned. First, one must worry that one’s ions are not
“hot”; that is, we are measuring thermochemical quantities and the ions should be at
thermal temperature for an accurate determination of acidity. We use argon to cool
our ions.
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The Research Proposal
Second, a drawback with multiple-acidic site bracketing, as we learned with uracil,
is that the more basic N3 ion can deprotonate a weak acid, which produces a strong
base, which can then deprotonate the N1H of thymine. The end result is that one
might never observe the (M-1) of the weak acid indicating proton transfer between
the N3 and the reference acid; instead, one sees the N1 of thymine, m/z 125.
Therefore, while the most acidic site will have a very accurate measurement, the less
acidic sites are, to be exact, a lower limit on acidity. Our proposed plan to circumvent
this problem is to use deuterated acids. The N3 ion will deprotonate the deuterated
acid; if the conjugate base deprotonates the N1H of thymine, then we will see the
deuterated thymine anionic product as a mass-to-charge ratio one mass unit higher
than deprotonated thymine! In this way, we hope to gain accurate values, even for the
less acidic site.
m/z
This abbreviation for mass to charge ratio is italicized (not bolded).
It is also common to anticipate obstacles and propose contingency plans in
synthetic work. In excerpt 13X, Johnson explains how he will deal with problems that might arise from a protic byproduct. Similarly, Vyvyan (excerpt 13Y)
points out an alternative sequence if the initial reaction proves unfruitful.
Contingency plans such as these suggest that the researcher is both farsighted
and resourceful, qualities that make them a worthwhile investment for a funding agency.
Excerpt 13X (Johnson, 2003)
The effect of this protic by-product on the proposed reaction will need to be determined. If necessary, removal of the solvent and alcohol in vacuo and re-dissolution of
the complexes (by means of a multichannel pipetter) should be feasible. Our glove box
is equipped with a vacuum inlet, so this procedure could be executed under rigorously
anhydrous conditions.
Excerpt 13Y (Vyvyan, 2001)
Should the proposed acid catalyzed 8-endo epoxide opening prove unfruitful, intermediate 49 could still be converted to heliannuol A through an alternative sequence
(Scheme 7). Specifically, conversion of 49 to the corresponding aryl trifl ate, deprotection of the diol, and reprotection of the secondary hydroxyl set up formation of the aryl
ether using the aryl etherification protocols developed by Buchwald45 and Hartwig.46
Heliannuol A 1 can be oxidized to produce heliannuol K 11 using any one of a number
of possible reagents.
Writing the Experimental Approach Section
471
Exercise 13.22
A fluent writer avoids using the same word over and over again. Suggest at least
three alternative choices for the italicized words in the following phrases. Look
through excerpts 13V–13Y for some ideas.
a. If problems arise, we will . . .
b. A possible problem is . . .
c. If plan A proves unsuccessful, then we will . . .
d. An alternative approach is to . . .
e. To test the feasibility, we will . . .
Exercise 13.23
Ideally, submove 3.3 both identifies a potential obstacle and offers a contingency
plan. Consider the following passages, all taken from submove 3.3 of Experimental
Approach sections. In each passage, identify the problem and, if present, the possible solution.
a. If problems develop with the interpretation of the magnetically aligned
nitroxide spin labeled-peptide bicelle data, we will incorporate the TOAC
spin label onto different residues of the peptides and repeat the experiments.
(From Lorigan, 2002)
b. Of course, if this protecting group were to be a problem, the compounds
would simply be protected as the alcohols and then oxidized at a later stage.
(From Hergenrother, 2002)
c. One drawback of immunoassays is the random occurrence of “false positives”
(detection of the analyte when it is not really in the sample) and “false negatives” (analyte is not detected when it is actually present). False positive results
are normally observed when there are interfering compounds in the matrix,
which may be removed by a simple cleaning procedure. False negative results
are observed when the concentration of the analyte in the sample is below the
detection limit of the immunoassay. Sample preparation procedures such as
SPE should prevent false negatives. False positive results may be eliminated by
verifying dubious results with a more sophisticated instrumental method such
as CZE/MS, which will be used only as a confirmatory test because it is more
expensive and a more tedious method. (From Aga, 2002)
d. The self-assembly of the dicopper complex may require careful adjustment of
conditions, such as solvent, order of addition, protonation state of the cysteine
thiol, and/or oxidation state of the copper starting material(s). The formation
of disulfide bonds and concomitant reduction of Cu(II) to Cu(I) through the
well-known redox process may require retaining the protecting group on the
cysteine thiol until after metal complex formation. (From Houser, 2001)
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The Research Proposal
Analyzing Writing
Writing a research proposal is a good way for you to learn how chemists
work—how they define meaningful problems, design experimental
approaches to investigate these problems, and anticipate how their research
will contribute reliable scientific knowledge to the community of chemists.
Writing research proposals, in other words, asks you to do chemistry.
—Beal and Trimbur (2001)
We finish our discussion of move 3 by calling your attention to the pointers placed
near selected excerpts above. These pointers and excerpts together highlight correct usages of the following words, punctuation, or other writing features:
■
irradiation vs. radiation (passage P1)
■
respectively (excerpt 13N)
■
stereochemistry terms (S) and (R) (excerpt 13N)
■
affect vs. effect (excerpt 13O)
■
which vs. that (excerpt 13P)
■
hyphenated two-word modifiers (excerpt 13R)
■
comprise vs. compose (excerpt 13R)
■
since vs. because (excerpt 13T)
To test your knowledge of these words and conventions, complete exercises
13.24–13.26.
Exercise 13.24
We have removed three hyphens from the following sentence. Where should the
hyphens be placed and why?
We will also begin to explore other biological interactions such as ligand
receptor binding, DNA hybridization, enzyme substrate interactions,
or protein DNA complexation to further evaluate the generality of our
approach. (From Lyon, 2000).
Exercise 13.25
Make the following sentence more concise by using the word “respectively”
correctly. Check units and punctuation as well.
Our calculations predict that the gas-phase acidity of thymine N1 should
be 331 kcal/mol and thymine N3 should be 343 kcal/mol. (Adapted from
Lee, 2001)
Writing the Experimental Approach Section
473
Exercise 13.26
Consider the italicized words or letters in the sentences below. If incorrect, correct
the error. If no changes are needed, indicate “correct as is”.
a. Because SPE is also a pre-concentration technique, the method detection limit
for the quantification of individual isomers could be improved by several
orders of magnitude. (Adapted from Aga, 2002)
b. The proposed work is comprised of three separate studies.
c. We have already demonstrated our ability to produce thermoresponsive
copolymer hydrogel particles which possess groups for protein attachment.
(Adapted from Lyon, 2000)
d. We anticipate that only the (S)-amino acid will be formed.
e. Our studies will explore whether or not increased Au atom energy can
effect the grain size on amine-terminated surfaces. (Adapted from
Spain, 1997)
We conclude this section by analyzing common verb tense–voice combinations
in move 3. Because move 3 describes work that will be done in the future,
future tense is most common. Future tense is used with both active and passive
voice:
Future–active
We will begin with a study of . . .
Our approach will examine . . .
We will measure the average size of . . .
Future–passive Films will be prepared by . . .
Several parameters will be explored.
These syntheses will be continued until . . .
Exercise 13.27
Consider the following sentences, adapted from CAREER proposals. Rewrite each
sentence in future tense and active voice.
a. “Differential imaging” is used as our next step to study cluster chemistry.
(From Sanov, 2002)
b. XPS is used to monitor changes in surface composition. (From Fairbrother,
2000)
c. Our coupling strategies utilized standard peptide coupling procedures.
(From Houser, 2001)
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The Research Proposal
Exercise 13.28
Consider the following passages, adapted from CAREER proposals. Each passage has one language or formatting error. Make corrections so that each passage
follows standard writing conventions.
a. We followed up our initial report with a second J. Am. Chem. Soc. paper,
which spectroscopically characterizes magnetically-oriented phospholipid
bilayers with EPR spectroscopy and discusses conditions for optimal bicelle
alignment at X-band (86). (Adapted from Lorigan, 2002)
b. A solid phase extraction (SPE) method that will isolate and fractionate
metolachlor and its oxanilic acid (OXA) and ethanesulfonic acid (ESA)
metabolites from soil and water will be developed. (Adapted from Aga, 2002)
c. Figure 4. Layer-by-layer polyelectrolyte adsorption. (Adapted from Lyon, 2000)
d. For example, hydrogen’s three isotopes, protium (H), deuterium (D), and
tritium (T), have substantial relative mass differences (1 amu, 2 amu, and
3 amu, respectively). (Adapted from Kohen, 2002)
e. For example, H2O has an (M-1) – ion of m/z 17 (HO –). (Adapted from Lee, 2001)
f. These findings were then successfully applied to a new interpretation of photoinduced electron transfer at similar interfaces, that are of importance in the
field of solar energy conversion.108 (Adapted from Lyon, 2000)
13C Writing on Your Own: Describe Your Proposed Methods
Write move 3 of your proposal. Be sure to (1) remind reader of preliminary results, (2)
describe procedures and instrumentation in a logical manner (e.g., sequentially, by underlying themes, by desired outcomes, or some combination), and (3) anticipate obstacles and
suggest alternatives with a contingency plan (that identifies both problems and possible
solutions). Use appropriate headings and subheadings in your writing.
13D Writing on Your Own: Complete the Experimental Approach Section
You are ready to complete the first full draft of your Experimental Approach section (moves
1, 2, and 3). Add headings, subheadings, and ordinal language, as needed, to organize your
ideas and to help your reader recognize the breadth and depth of your proposed work.
You may need to make small changes when combining the three parts to be sure they fit
seamlessly.
Review your written work (see chapter 18) before you submit it for peer review or to
your instructor.
Writing the Experimental Approach Section
475
Chapter Review
To judge what you’ve learned from this chapter, define each of the following terms
and explain its importance, in the context of this chapter, to a friend or chemistry
colleague who is new to the field:
computer-generated graphics
literature values
prior accomplishments
conceptual framework
obstacles
promising results
contingency plan
preliminary results
text boxes
Also explain the following to a chemistry colleague who has not yet given
much thought to writing the Experimental Approach section of a Project
Description:
■
Main purpose of the Experimental Approach section
■
Differences between moves 1 and 2: share prior accomplishments and share
preliminary results
■
Connections between collaborative relationships and demonstration of
expertise
■
Ways to share your proposed methodology (move 3)
■
Level of detail to include in your proposed methodology (move 3)
■
Reasons for anticipating obstacles in your proposed research
Additional Exercises
Exercise 13.29
Reflect on what you have learned from this chapter. Select one of the reflection
tasks below and write a thoughtful and thorough response:
a. Reflect on two underlying themes of the Experimental Approach section:
to demonstrate (1) the expertise of the researcher and (2) the plausibility
and promise of the proposed research. At this point in your professional
development,
■
■
■
476
What is the best way to demonstrate your expertise?
How will you demonstrate the plausibility and promise of your proposed
research?
What steps will you take to build reviewers’ confidence in you and your
research plan?
The Research Proposal
b. Research proposals require that writers (1) reveal potential obstacles in the
design and methodology of the proposed work and (2) suggest contingency
plans.
■
■
■
How is it possible that a proposal can be strengthened by the inclusion
of possible obstacles and/or weaknesses?
How can drawbacks be introduced to establish a writer’s expertise and
abilities?
How important do you think contingency plans are for reviewers of
research proposals?
c. Reflect on the similarities and differences between the Methods section
of a journal article and research proposal.
■
■
■
What are the similarities?
What are the differences?
What will you do to make sure the Experimental Approach section
of your proposal meets reviewers’ expectations?
Writing the Experimental Approach Section
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14
Writing the Outcomes and Impacts Section
A well-developed proposal shows that the investigator has grasped
a problem well enough to justify second-party sponsorship.
—Paradis and Zimmerman (1997)
All good proposals must come to an end. In this chapter, we examine conventional
ways in which authors summarize and conclude their Project Descriptions. We
consider project timelines, lists of expected outcomes, and statements of broader
impacts. By the end of this chapter, you should be able to
■
Develop a project timeline
■
Generate a list of expected outcomes
■
Suggest broader impacts of your proposed work
■
Reinforce the importance of your proposed work in concluding remarks
Staying on Track
This chapter covers what is normally presented in the last major section of the Project
Description. Common level 1 headings in this section are
PROJECT TIMELINE
EXPECTED OUTCOMES
CONCLUSIONS
As you work through the chapter, you will write the closing section of your own
Project Description. The Writing on Your Own tasks throughout the chapter
guide you step by step as you do the following:
14A Create a project timeline
14B Create a list of expected outcomes
14C Conclude the proposed work
14D Complete the Outcomes and Impacts section
Like the previous sections of the Project Description (chapters 12 and 13), there is
no one right way to end a proposal. However, proposal guidelines often instruct
authors to include a projected timeline, a list of expected outcomes, a summary
of objectives, and/or a statement of relevance or broader impacts in their concluding remarks. For example, the ACS Division of Analytical Chemistry Graduate
Fellowship announcement (excerpt 11A) asks for a statement that links “the relevance of [the proposed] work to analytical chemistry.” The NSF Grant Proposal
Guide (see excerpt 15B) asks for “objectives for the period of the proposed work,”
their “expected significance,” and their “relationship to longer-term goals of the
PI’s project.” Moreover, the PI must describe “as an integral part of the narrative, the broader impacts of the proposed activities.” Not surprisingly, each of the
authors of our 22 CAREER proposals approached this task slightly differently. We
examine several of their approaches in this chapter.
Reading and Analyzing Writing
We begin with an excerpt that you can read and analyze on your own (excerpt
14A), specifically, the conclusion to Harpp’s proposal regarding plume-ridge interaction in the Galápagos. She includes a formal timeline (titled “Project Schedule”)
and conclusions for her work.
Exercise 14.1
Read excerpt 14A and answer the following questions:
a. How does the author preface the year-by-year timeline? What purpose does
the preface serve?
b. How detailed is the timeline? What kinds of details are included and
excluded?
c. Note that the timeline is written in a “to do” list fashion. Check to be sure that
the author uses parallel language in her list. Find five phrases that are parallel
to the opening phrase in the Year One description (i.e., Refinement of . . .).
d. Why do you think it is acceptable to write the timeline in a “to do” list fashion but the Conclusions section in complete sentences?
e. The author stresses importance again in her Conclusions section. Give two
examples; what purpose is served by each example?
f. Suggest synonyms for the words “importance” and “important.”
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The Research Proposal
Excerpt 14A (Harpp, 1998)
PROJECT SCHEDULE
The schedule for this project is designed to permit participation by undergraduates
such that students will have their own project, sufficient time to complete the analytical work, and the opportunity to present results at a national meeting. The fieldwork
is divided into two trips to fit the academic calendar (travel during winter break), and
to increase the number of opportunities for students to participate in a unique field
experience.
Year One: Refinement of sample preparation and analytical techniques for trace
element analysis in ocean island basalts using existing samples from the Galápagos.
Compilation of existing geochemical data for Pinta and Marchena Islands. Training of
students in analytical techniques, preparation for fieldwork.
Year Two: Field excursion to Wolf and Darwin Islands (24 days total; 6 days on each
island). Petrographic examination of samples at Lawrence University, initial analysis of
trace elements by ICP-MS at Lawrence University (up to 100 samples).
Year Three: Complete analysis of trace elements by ICP-MS at Lawrence University;
analysis of major elements by XRF at Macalester College (up to 100 samples); determination of Sr, Nd, and Pb isotopic ratios of a selection of Wolf and Darwin samples by TIMS
at Cornell (up to 30 samples). Interpretation of geochemical data, modeling of melting
parameters. Presentation of results at Fall AGU meeting by undergraduate student(s).
Preparation for fieldwork.
Year Four: Field excursion to Genovesa Island (24 days total; 12 on the island).
Petrographic examination of samples at Lawrence University; initial analysis of trace
elements by ICP-MS at Lawrence University (up to 100 samples).
Year Five: Complete analysis of trace elements by ICP-MS at Lawrence University;
analysis of major elements by XRF at Macalester College (up to 100 samples); determination of Sr, Nd, and Pb isotopic ratios of a selection of Wolf and Darwin samples by TIMS
at Cornell (up to 30 samples). Interpretation of geochemical data, modeling of melting
parameters. Presentation of results at Fall AGU meeting by undergraduate student(s).
Preparation of final plume-ridge interaction synthesis paper for publication with student
authors.
CONCLUSIONS
Detailed geological and geochemical examination of Wolf, Darwin, and Genovesa
Islands will provide important information regarding the volcanic evolution of these
features, and their relationship to the main Galápagos archipelago via the Morgan
pipeline hypothesis, the leaky fault model, or the mini-hotspot/near-ridge volcanism
model. The collected data and mapping information will yield important information regarding shallow mantle flow, hotspot dynamics, and plume-ridge interactions.
Finally, detailed information regarding Wolf, Darwin, and Genovesa Islands will
serve as an important database for current biodiversity and evolutionary studies in the
Galápagos.
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Six or 6?
In most cases, use the number form rather than the word form for numbers with units
of time and measure (e.g., 6 days, not six days). Use the word form with other units (e.g.,
two trips) unless the number is 10 or greater (e.g., 12 samples). (See Numbers and Units in
appendix A.)
Analyzing Organization
The move structure for the Outcomes and Impacts section of the Project
Description is shown in figure 14.1. The first two moves summarize the proposed
work by highlighting expected achievements. Typically, no new information is
provided in these moves; rather, their purpose is to summarize deliverables or
tangible accomplishments that will result from the work. Examples include the
delivery of a more efficient synthesis, an improved analytical procedure, or a
novel application of an instrument. Deliverables also include the dissemination
of findings through conference presentations, publications, and patents, allowing
the larger scientific community to learn about your work.
Deliverables
The more tangible products of a research project, such as a novel synthesis.
Deliverables also include the dissemination of findings through publications, patents,
and conference presentations.
1. Present Project Timeline
2. List Expected Outcomes
3. Conclude the Proposed Work
3.1 Reiterate goals and importance
3.2 Address broader impacts
Figure 14.1 A visual representation of the suggested move structure for an
Outcomes and Impacts section of the Project Description.
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The Research Proposal
Move 3 concludes the proposal and focuses on the project’s broader impacts,
allowing investigators one more chance to stress the importance of the work.
The Outcomes and Impacts section, like the Conclusions section in a journal article, broadens its scope to address a scientific, rather than an expert,
audience.
With the move structure for the Outcomes and Impacts section in mind, we
are ready to analyze the three moves in more detail and consider headings for
each move.
Move 1: Present a Project Timeline
A convenient way to summarize the more tangible accomplishments of your work
is to present them in a timeline. Recall the specific-achievable-measurable (SAM)
test for research objectives introduced in chapter 12; a timeline helps reviewers
(and you) evaluate whether your project goals are achievable within the funding period. The start of this move is usually demarked with a level 1 heading.
Common headings for move 1 are shown in table 14.1.
Analyzing Excerpts
A realistic time schedule becomes an effective argument. It suggests to
readers that you understand how much time your project will take and
that you are not promising miracles just to win approval.
—Adapted from Houp et al. (2006)
Let’s consider a few examples to see how authors address timelines in their proposals. Harpp (excerpt 14A) presents a year-by-year synopsis of her project,
listing tangible accomplishments in each time interval (e.g., compilation of existing data, analysis of up to 100 samples, presentation of results at a conference,
and preparation of the final plume-ridge paper). Note the language in the timeline; it reads much like a “to do” list, using phrases rather than full sentences
Table 14.1 Common level 1 headings for move 1 of the Outcomes and
Impacts section.
PROJECT TIMELINE
PLAN OF WORK
PROJECT SCHEDULE
PROPOSED WORK PLAN
Writing the Outcomes and Impacts Section
483
(e.g., “Training of students in analytical techniques, preparation for fieldwork”).
Many of the tasks begin with nominalizations:
refinement of ____
analysis of ____
examination of ____
presentation of ____
preparation of ____
interpretation of ____
Nominalizations
A noun formed from another part of speech. For example, the noun interpretation comes
from the verb interpret. (See appendix A and table 2.2.)
Finney (excerpt 14B) and Sanov (excerpt 14C) also include timelines, but they
integrate them into the running prose of their text. As you read their timelines,
note their use of hedging language. (Indeed, it is difficult not to hedge when
describing what you will be doing over the next 5 years!) Finney, for example,
anticipates that the synthesis of the fluorophore will take 6 months (in light of his
many other responsibilities), while the library synthesis and fluorescence characterization are anticipated to take 18 months. Sanov begins by acknowledging how
ambitious his project is and points out that his progress will be guided by currently
unknown intermediate results. Nevertheless, he does his best to provide strategic
landmarks, and he describes his hope to start tackling bimolecular reactions in the
second half of the award period.
Hedging
Hedging is used to soften a writer’s stance. (See appendix A.)
Excerpt 14B (Finney, 1999)
ANTICIPATED TIMELINE FOR NEAR-TERM RESEARCH OBJECTIVES
The immediate goal of fully characterizing the parent Hg2+-responsive fluorescent
chemosensor, which will entail 1H NMR and fluorescence titration experiments, isolation and characterization of the 1:1 Hg2+:ligand complex, and fluorescence lifetime
measurements of the simple diol/carbonate pair, is expected to be complete within 6
months. (This work will be the primary responsibility of the graduate student currently
on the project, Sherri McFarland.)
The synthesis of biaryl fluorophores exhibiting visible fluorescence will be the
responsibility of the PI (Nat Finney) and will begin within a month. The synthesis and
complete characterization of the proposed fluorophores are anticipated to take 6 months,
in light of teaching, advising, and grant-writing responsibilities.
The synthesis of the combinatorial library of fluorescent chemosensors will be
assigned to an incoming graduate student. Initial work will focus on validation of the
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The Research Proposal
synthetic chemistry, which is anticipated to take 6 months. Upon completion of her
studies on the parent system, Sherri McFarland will join the new graduate student on
this aspect of the project. Library synthesis and fluorescence characterization are anticipated to be complete within 18 months.
“and” (with no comma)
No comma is needed before “and” when the sentence has a single subject and two verbs
(e.g., I read and revise). (See Commas in appendix A.)
Excerpt 14C (Sanov, 2002)
TIMELINE
It is recognized that the range of the experiments described in this proposal is very
ambitious. But this is a long-term program at the frontier of science, and I must be
guided by intermediate results to decide which directions merit the greatest attention.
Nonetheless, I envision the following strategic landmarks. Within several months, we
will complete the diagnostic experiments on I– and other atomic anions. By the end
of 2001, we will have carried out the studies of O2– and S2– and should soon have the
results on the OCS – hydration. In 2002, we will begin the time-resolved experiments on
(OCS)2– and continue with reaction dynamics and alignment studies in other systems.
Bimolecular reactions in clusters are our most ambitious goal, which I hope to start tackling in the second half of the award period.
“. . . , and” (with a comma)
A comma is needed before “and” when it joins two complete sentences (e.g., I read, and I
revise). (See Commas in appendix A.)
Exercise 14.2
Reread excerpts 14B and 14C. Then answer the following questions:
a. How detailed are the two excerpts in specifying time periods and/or the passage of time? Give some examples.
b. What features distinguish these timelines from one another? In other words,
what are the defining characteristics of each of these timelines?
c. Do the two researchers take advantage of the opportunity to stress the importance of their work one last time? If so, what language do they use to emphasize the value of their proposed work?
Writing the Outcomes and Impacts Section
485
Timelines can also be portrayed in charts or figures, as illustrated in excerpt
14D. In fact, charts and figures represent excellent ways to illustrate how smaller,
individual projects contribute to larger research goals and how smaller projects
complement one another and overlap in time. (Note: In excerpt 14D, Kohen uses
the following abbreviations in his chart, each defined previously in the proposal:
hydrogen (H), tritium (T), deuterium (D), kinetic isotope effect (KIE), dihydrofolate reductase (a relatively small protein) (DHFR), and wild type (WT).)
Excerpt 14D (Kohen, 2002)
Timetable for work plan. The work plan spans five years and involves eight related
projects (Figure 3). Enzyme preparation, syntheses of H/T- and D/T-labeled NADPH,
and preparation of high resolution crystals have been started, or will be started, in the
early stages of the project. Studies related to KIEs, the temperature dependence of KIEs,
and DHFR dynamics will take place in years 1–5; modeling and interpretation of the
results will take place in years 2–5.
Five or 5?
In a single sentence, refer to numbers (as either numerals or words) in the same way. In
excerpt 14D, “five years” was used instead of “5 years” to be consistent with “eight projects.”
(See Numbers and Units in appendix A.)
Year:
0
1. Enzyme
preparation
2. Synthesis
3. KIEs and
kinetic
complexity
1
WT from
Penn. State
H/T
labels
2
on-site
preparation
4
5
on-site
mutagenesis
D/T
labels
H/T
KIEs
4. Examining
Swain-Schaad
relations
D/T
exponential
& relationships
KIEs
5. Temperature
dependency
of KIEs
KIEs from
0 to 50 C°
6. Studies of
mutants
7. DHFR's
dynamics
studies
3
high resolution
crystals of WT
8. Modeling and
interpretation
w/ reduced kinetic complexity
w/ altered dynamics
WT dynamics
by B-factors
dynamics of mutants by
NMR and X-ray
apply various theories
to results
focus on a
unique model
Figure 3. Timetable for work plan.
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The Research Proposal
Exercise 14.3
Excerpts 14A–14D illustrate three different ways to present a timeline: in a yearby-year list, formal prose, or a figure. All three approaches are appropriate. Which
approach do you prefer and why?
Analyzing Writing
We used pointers near excerpts 14A–14D to call your attention to correct usages
of the following writing features:
■
numbers and units (excerpts 14A and 14D)
■
nominalizations (excerpt 14A).
■
hedging (excerpts 14B and 14C)
■
commas (excerpts 14B and 14C)
To test your knowledge of some of these features, complete exercises 14.4 and
14.5. Refer back to the excerpts and pointers as needed.
Exercise 14.4
The following sentences were adapted from project timelines. Correct the errors
in each sentence.
a. In the first year, we will discover at least five new compounds.
b. The initial project is expected to take 2 years and will involve the synthesis
of six new compounds.
c. In Year 2, we will collect fifty samples at the Grand Canyon site; in Year 3, we
will collect fifty samples at the Yosemite site.
d. We will begin with time-resolved experiments, and continue with reaction
dynamics and alignment studies.
Exercise 14.5
Nominalize each of the following verbs; specify the noun that can be formed from
the verb:
a. to prepare
b. to synthesize
c. to analyze
d. to present
e. to interpret
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Table 14.2 Common functions of different verb tense–voice combinations in move 1 of
the Outcomes and Impacts section of the Project Description.
Function
Tense–Voice
Combination
Example
Present timeline (in
narrative form)
Present–active
The work spans five years and involves
eight related projects. (From Kohen, 2002)
Present–passive
A comprehensive study of . . . has been
presented.
Future–active
Studies related to . . . will be initiated in
Year 3.
Future
perfect–active
By the end of 2009, we will have completed
the studies on . . .
We conclude our discussion of move 1 by considering verb tense and voice combinations. Present and future tenses, with either active or passive voice, are commonly used in narrative timelines (e.g., excerpt 14B and 14C), as summarized
in table 14.2. The timeline itself is often a list of fragments that need not contain
verbs, as illustrated in the following timeline adapted from Harpp (1998):
Year One Refinement of sample preparation and analytical techniques
Training of students in analytical techniques
Year Two Field excursion to Wolf and Darwin Islands
14A Writing on Your Own: Create a Project Timeline
Draft a timeline for your proposed research. Decide if you want to present your timeline in
running prose, as a list, or as a graphic (chart or figure). Include a heading for your timeline.
Move 2: List Expected Outcomes
In addition to a timeline, a second way to summarize anticipated accomplishments is to list your expected outcomes. Expected outcomes are measurable
achievements that link back to the measurable objectives listed at the start of the
proposal. Recall that the Project Description often starts out with a list of specific,
achievable, and measurable (SAM) objectives. Timelines attest to the achievability
of the objectives; outcomes attest to their measurability.
Move 2 is often demarked with a level 1 heading (see table 14.3). In some
headings, the term “outcome” is used explicitly (e.g., EXPECTED OUTCOMES).
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The Research Proposal
Table 14.3 Common level 1 headings for move 2 of the Outcomes and
Impacts section.
EXPECTED OUTCOMES
PROJECT OUTCOMES
EXPECTED FINDINGS
SUMMARY
PROJECT DELIVERABLES
SUMMARY OF RESEARCH PLAN
In other cases, the heading is more generic (e.g., SUMMARY). In the latter case,
the outcomes are integrated into an overall summary of the proposed work.
Analyzing Excerpts
We include two excerpts for you to consider. Johnson (excerpt 14E) lists expected
outcomes in his proposed Lewis acid–promoted [3+2] cycloaddition reactions.
Projected outcomes include new strategies (for promoting cycloaddition reactions),
a diverse range of hetereocycles (to be used as future chiral building blocks), and
new approaches (for identifying additional catalysts). Patrick (excerpt 14F) lists
expected outcomes for his liquid crystal imprinting investigations. His outcomes
include refinement and extensions of current techniques, improved fundamental
understanding (of liquid crystal imprinting mechanisms), and preparations of new
types of films and film materials. Both lists are short and succinct. Moreover, both
investigators preface their lists with a short paragraph that reiterates the overall
goals of the proposed work.
Excerpt 14E (Johnson, 2003)
SUMMARY
Lewis acid-promoted [3+2] cycloadditions of aziridines and epoxides proceeding via
carbon-carbon bond cleavage of three-membered ring heterocycles are demonstrated for
the first time. This proposal details plans for extending these initial results into a general
synthetic method for the enantioselective synthesis of structurally diverse pyrrolidine- and
tetrahydrofuran-containing organic compounds. Expected outcomes of the proposed
work will include
1. A variety of strategies for effecting dipolar cycloadditions from stable, neutral precursors, including carbon-carbon bond heterolysis induced by Lewis acidic metal
complexes and chiral organic catalysts;
2. A diverse range of heterocycles and other chiral building blocks that can be generated
by this cycloaddition strategy;
3. Focused approaches for rapidly evaluating metal complexes that are candidates to
catalyze the cycloadditions.
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Excerpt 14F (Patrick, 2000)
SUMMARY OF THE RESEARCH PLAN
The research plan is organized around a set of well-defined model systems and a limited
number of detailed experiments. The experiments are designed to progress over a fiveyear period from fundamental studies on model systems to development of thin film
materials with potential practical applications. Together they will form a coherent bond
of film growth using LCI with a variety of molecular building and LC solvents. The
expected outcomes of this work will be
1. Refinement and extension of the LCI technique to include additional building blocks
and LC solvents.
2. Improved fundamental understanding of LC-surface interactions.
3. Preparation of a new type of nanostructured composite thin film in which one component possesses unidirectional order while the other component is randomly oriented.
4. Preparation of thin film materials for use as re-writable anchoring.
Parallelism in Enumerated Lists
Note the different, and correct, uses of parallel language, numbering, and punctuation in
the lists of expected outcomes in excepts 14E and 14F. (See appendix A.)
Exercise 14.6
Examine excerpts 14E and 14F. What do you notice about the following features
of the authors’ writing? Generalize a rule for each feature that will assist you in
your own writing.
a. Lack of punctuation after “will include” and “will be” just before lists begin
b. Punctuation at the end of listed items
c. Different forms of parallelism in lists
Exercise 14.7
In both excerpts 14E and 14F, the authors preface their lists with a short
paragraph.
a. What kind of information is included in these paragraphs?
b. Do you notice more similarities or differences between these two paragraphs?
Explain.
c. How does the information in these short paragraphs influence the choice of
heading in each excerpt (e.g., “Summary” rather than “Expected Outcomes”)?
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The Research Proposal
Exercise 14.8
Dyer (excerpt 14G) uses a list of questions rather than a list of outcomes to accomplish move 2. Select four of his questions and rewrite them as expected outcomes.
Be sure to use parallel language and formatting in your list.
Excerpt 14G (Dyer, 2001)
SUMMARY
The research activities presented here will represent a significant departure from previous approaches to polar order in organic thin films. This work will address several
important questions: First, is it possible to induce thermodynamically stable polar
order along the LC director axis? Second, how do surface interactions affect the global
orientation of liquid crystals? Third, can hydrogen bonding force the growth and polar
orientation of noncovalent polymer networks? Fourth, can we develop and utilize the
synthetic methodology for growing densely packed polymer brushes? Fifth, will polymer
brushes adopt conformations that yield a permanent polarization density? And sixth, to
what extent may we control properties such as second order NLO, pyroelectricity, and
piezoelectricity in organic thin films?
Analyzing Writing
We used a pointer to highlight parallelism in enumerated lists in excerpts 14E
and 14F. Test your knowledge of parallelism by completing exercise 14.9.
Exercise 14.9
Consider the following first draft of expected outcomes (adapted from
Hergenrother, 2002). Convert it to a final list of expected outcomes, as it might
appear in a finished proposal. Be sure to use parallel language, punctuation, and
numbering in the final list.
Expected outcomes for proposal:
■
We will synthesize a 6,000-member focused library designed to inhibit the caspase
family of cysteine proteases involved in apoptosis.
■
If 6,000-member focused library is successful, extend it to a library of 60,000
members.
■
synthesis of a 2,400-member dihydropyridone-based primary library containing four
cyclic scaffolds, screened against apoptotic proteins
■
We will extend the primary library to >30,000 compounds
Writing the Outcomes and Impacts Section
491
We conclude our discussion of move 2 by considering verb tense and voice combinations used in this move. The sentence that introduces expected outcomes is
usually written in future tense and active voice with “expected outcomes” as the
subject of the sentence:
Future–active The expected outcomes of this work will be . . .
The expected outcomes of this work will include . . .
The expected outcomes themselves are often presented in an enumerated list.
Like the timeline in move 1, the list often contains fragments with few or no
verbs, as illustrated in the following list of expected outcomes adapted from
Johnson (2003):
1. A variety of strategies for effecting dipolar cycloadditions
2. A diverse range of heterocycles and other chiral building blocks
3. Focused approaches for rapidly evaluating metal complexes
14B Writing on Your Own: Create a List of Expected Outcomes
Draft a list of expected outcomes for your proposed research. Strive to link your outcomes to the list of project goals and objectives that you created in the first section of the
proposal (see Writing on Your Own task 12B). Make sure that you list outcomes in a parallel
fashion. Include a heading and a brief introduction.
Move 3: Conclude the Proposed Work
The last move concludes the proposal. This is accomplished in two submoves. This
first submove reiterates project goals and stresses (once again) the expected accomplishments and importance of the proposed work. In the second submove, authors
take a step back to look at the broader impacts of the project. Who are the beneficiaries of this new knowledge, synthesis, methodology, or instrumentation? How does
the work benefit the larger scientific community and general public? Most authors
try to address questions such as these in their closing remarks. Move 3 is typically
signaled with a level 1 heading. Common headings are shown in table 14.4.
Gender-Neutral Language
The ACS Style Guide urges writers to use gender-neutral language. When, for example, identifying broader impacts, refer to the general public, people, or humankind, rather than mankind.
See The ACS Style Guide for other suggestions.
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The Research Proposal
Table 14.4 Common level 1 headings for move 3 of the Outcomes and
Impacts section.
CONCLUSIONS
RESEARCH SUMMARY
CONCLUSIONS AND IMPACTS
SUMMARY
IMPACTS AND SIGNIFICANCE
Analyzing Excerpts
To analyze how authors conclude their proposals, we consider three excerpts. In
each case, the author begins with a reminder of project goals and objectives—
reemphasizing importance—and concludes with a statement of broader impacts.
For example, Harpp (excerpt 14A) begins her Conclusions section by reemphasizing the important information that will be gained by a detailed examination of
islands in the Galápagos archipelago. She ends her Conclusions by emphasizing
that her work will serve as an important database for others studying biodiversity
and evolution in this area. Walker (excerpt 14H) uses his Research Summary
section to remind us how his proposed work will elucidate dynamic solvation
processes. He concludes by pointing out that his work can lead to improved predictive models with the potential to significantly impact the modeling of interfacial processes ranging from electron transfer reactions to protein folding. Rose-Petruck
(excerpt 14I) begins by reiterating the immediate impacts of his research: a clearer
understanding of ligand motions in the gas and liquid phases. He finishes by stating that his work may enable a view into the very center of chemical processes
(ultrafast structural motion and dynamics), may inspire others to develop ultrafast
X-ray systems, and will have applications in chemical and biomedical industries.
Excerpt 14H (Walker, 2001)
RESEARCH SUMMARY
Fruitful interplay between experiment and theory has led to an increasingly detailed
understanding of equilibrium and dynamic solvation properties in bulk solution.
However, applying these ideas to solvent-solute and surface-solute interactions at interfaces is not straightforward due to the inherent anisotropic, short-range forces found in
these environments. Our research will examine how different solvents and substrates
conspire to alter solution-phase surface chemistry from the bulk solution limit. In particular, we intend to determine systematically and quantitatively the origins of interfacial
polarity at solid-liquid interfaces as well as identify how surface-induced polar ordering
affects dynamic properties of interfacial environments. . . .
We hope that our results will aid in developing predictive models of interfacial
permittivity. . . . One specific objective will be to search for evidence of dry layers at
hydrophobic-aqueous boundaries. If such layers form (and if our experiments can successfully characterize their extent), our results will impact significantly the modeling of
processes ranging from electron transfer to protein folding.
Writing the Outcomes and Impacts Section
493
Split Infinitives
Avoid split infinitives unless needed for clarity.
Ambiguous: to develop completely new compounds
Unambiguous: to completely develop new compounds
(See appendix A.)
Excerpt 14I (Rose-Petruck, 2000)
IMPACT AND BROADER SIGNIFICANCE
The immediate impact of this research will be a clearer understanding of ligand
motions during photoelimination reactions. In particular, comparative studies of
molecular motions in the gas phase (using ultrafast electron diffraction) and in the
liquid phase should become a source of very detailed understanding of the influence
of solvation on chemical processes. Such combined studies in collaboration with Peter
Weber, Dept. of Chemistry, Brown University are planned.
In general, UXAS opens a new spectroscopic window for the direct ultrafast timeresolved observation of molecular motions during chemical reactions. Its applications
will range from physical to organometallic and bioinorganic chemistry. It will enable
a “view” into the very center of chemical processes—ultrafast structural motion and
dynamics. The demonstration that ultrafast X-ray investigations can be carried out
with laboratory-based equipment will, hopefully, inspire others to build and apply such
ultrafast systems themselves. This research is embedded in related investigations that
are centered around the development of ultrashort and ultrabright laboratory based
X-ray sources and their applications to chemical biomedical problems.
X-ray, UV–vis
Note that the “r” in X-ray is not capitalized. X-ray must be followed by a noun (e.g., X-ray
sources).
UV–vis, too, must be followed by a noun (e.g., UV–vis spectroscopy).
Exercise 14.10
Reexamine excerpts 14H and 14I.
a. The author of excerpt 14H uses personal pronouns (we, our), while the author
of excerpt 14I does not. Both writing styles are acceptable. Which style do
you prefer and why?
b. What headings do the authors use to conclude their Project Descriptions?
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The Research Proposal
Exercise 14.11
Another example of move 3 is shown in excerpt 14J. Read the excerpt and answer
the following questions:
a. What are the primary goals of Tuckerman’s research?
b. How does he emphasize the importance of his work?
c. What broader impacts does Tuckerman address? Who may potentially
benefit from this project?
d. Explain the purpose of the author’s last sentence.
e. Based on the heading used, how do you think Tuckerman formatted other
headings in his proposal?
Excerpt 14J (Tuckerman, 1999)
7. SUMMARY
A proposal for the comprehensive study of chemical processes in a variety of important
condensed-phase systems using modern theoretical methodology has been presented.
The primary goals of the research are to provide microscopic information on the mechanisms and structural and dynamical properties of the chemical systems proposed for
investigation, to test the applicability of modern ab initio molecular dynamics (MD) by
comparison with experiment, and to develop and apply novel ab initio MD techniques
in simulating complex chemical systems. The proposed research will contribute to the
forefront of modern theoretical chemistry and address a number of important technological issues. The PI has carefully attempted to demonstrate his knowledge, ability, and
resources to carry out the proposed research projects.
Ab initio
According to The ACS Style Guide, common Latin phrases such as “ab initio” should not be
italicized or bolded (or placed inside quotation marks).
As mentioned in chapter 11, the term “broader impacts” also includes human
impacts (i.e., how the proposed work will impact students and prepare them to
be future scientists). For example, Aga (excerpt 14A) addresses students in her
Project Schedule section (“Students will have their own project, sufficient time to
complete the analytical work, and the opportunity to present results at a national
meeting.”). Similarly, Finney (excerpt 14B) mentions one graduate student by
name and another “new” graduate student who will join the project. These are
just two examples. In general, authors describe human impacts by (1) anticipating
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how many students will be involved in the project and for how long, (2) describing new lecture or laboratory curricula that will be developed, (3) listing specific
skills that students will learn, and (4) identifying opportunities that students will
have to share their results with the larger scientific community (e.g., through
conference presentations and publications).
Analyzing Writing
We used pointers in excerpts 14H–14J to call your attention to the following
writing features in this move (each described in more detail elsewhere in the
textbook):
■
use of split infinitives (excerpt 14H)
■
use of UV–vis and X-ray (excerpt 14I)
■
use of ab initio (excerpt 14J)
To test your knowledge of these features, complete exercises 14.12 and 14.13.
Refer to the excerpts and pointers as needed.
Exercise 14.12
Rewrite the following sentences so they adhere to conventional writing practices
in chemistry:
a. Our work is centered around the development of ultrashort and ultrabright
X-Ray sources.
b. We will use ab initio molecular dynamics to simulate complex chemical
systems.
c. FTIR and UV–VIS will be used to probe the mechanisms of the reaction.
Exercise 14.13
Identify the split infinitives in the following sentences. Rewrite each sentence
without a split infinitive, unless the change will create unwanted ambiguity.
a. One purpose of move 3 is to clearly restate the importance of the proposed
work.
b. Compounds will be chosen for their ability to efficiently catalyze the cycloaddition reactions.
c. We intend to systematically investigate the origins of interfacial polarity.
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The Research Proposal
Table 14.5 Common functions of different verb tense–voice combinations in move 3 of
the Outcomes and Impacts section of the Project Description.
Function
Tense–Voice
Combination
Example
Reiterate goals and
importance
Present–active
The primary goals of this research are to . . .
Present
perfect–passive
A comprehensive study of . . . has been
presented.
Future–active
A detailed examination of . . . will possibly
shed new light on . . .
Our research will examine . . .
Address broader
impacts
Future–active
If successful, our results will contribute
to . . .
Our findings will potentially impact . . .
We conclude our discussion of move 3 by considering verb tense and voice
combinations commonly used in this move (summarized in table 14.5). Present
tense, present perfect, and future tense are used to reiterate goals. Future tense
is used most often to state broader impacts. Active voice is common throughout
the move, and personal pronouns (e.g., we and our) may be used at the authors’
discretion.
Exercise 14.14
The following sentences were adapted from the concluding remarks of Project
Descriptions. Select the most appropriate verb tense in each sentence. Explain
your choice. (Note: There may be more than one correct answer.)
a. The proposed goals represent/have represented/will represent a significant
departure from previous approaches to polar order in organic thin films.
(Adapted from Dyer, 2001)
b. The proposed synthesis benefits/has benefited/will benefit biochemists in both
academia and industry.
c. To contribute to students’ research skills, the proposed work involves/
has involved/will involve three undergraduate students in each year of the
project.
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14C Writing on Your Own: Conclude the Proposed Work
Write a conclusion for your Project Description that (1) reiterates project goals and importance and (2) addresses the broader impacts of the work. Take advantage of your last
opportunity to stress the importance of your work.
14D Writing on Your Own: Complete the Outcomes and Impacts Section
Integrate your timeline, list of expected outcomes, and conclusions into a final draft of the
Outcomes and Impacts section. Edit and proofread the section so that it is ready for peer
review or final submission (see chapter 18).
Chapter Review
Check your understanding of what you’ve learned in this chapter by defi ning
each of the following terms and explaining its importance, in the context of the
chapter, to a friend or chemistry colleague who is new to the field:
broader impacts
deliverables
dissemination of results
expected outcomes
hedging language
nominalizations
parallelism
split infinitives
tangibles
timeline
Also explain the following to a chemistry colleague who has not yet given
much thought to writing the Outcomes and Impacts section of a Project
Description:
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■
Main purpose(s) of the Outcomes and Impacts section
■
Purpose of the three moves in the section
■